Maximum Compression (previous updates)

Previous updates - before 2006

30-December-2005 : A major site update at the end of the year!. There are new versions for both the current #1 and #2 program (WinRK and PAsQDa) plus a new piece of software storming the charts : PAQ7 by Matt Mahoney. PAQ7 is a totally redesigned PAQ6 variant with some nice features like jpeg and bitmap compression for embedded images in Excel, Word Documents (have a look at the DOC test...), pdf-files and executables. Currently PAQ7 has no optimizations for text, executables or wav files, when it gets some filters/models for these filetypes I think it will have the potential to take 1st place in both SFC and MFC.

Added WinRK 3.0.2, PAsQDa 4.3c, PAQ7, PAQAR 4.1, 7-Zip 4.32, WinHKI 1.60, LZPX(J) 1.0a, CHILE 0.3d, QazaR 0.0 pre4b, KZIP 23-11-2005 and PIMPLE 1.0b6 to the SFC test. PAQAR, WinHKI, KZIP, PAsQDa, 7-Zip, WinRK (PWCM) show no or little changes in compression sizes compared to previous tested version. Chile, QAZAR and PAQ7 are new, LZPX(J) is an improved version of LZPX 1.5b with better handling of non-redundant (e.g. pre-compressed) data. PIMPLE now has some switch settings improving compression. On 'best overall compression program' WinRK is ranked 1st, PAQ7 2nd and PAsQDa 3th. For an overview of the single file compression results have a look at the SFC summary pages.

The 'real life' multiple files results can be viewed on the MFC pages. WinRK now even scores reasonably well on efficiency with is 'fastest' profile, but the 'maximum' profile is not able to complete the test (we are investigating the problem). PAQ7 doesn't show it's full potential yet, but this will change when the exe,wav,txt models are in place...
26-November-2005 : Added PPMVC 1.0 and PIMPLE 1.0test1. PIMPLE is the replacement / successor of LZPX 1.6pre1, LZPX 1.5b will be the latest released LZPX version (main design goal: speed). PIMPLE is an experimental highly optimised PAQ-like encoder ("PAQ-like" meaning non stationary bit oriented PPM with full blending) optimised for higher compression, but still good speed. PIMPLE takes place #30 in SFC). Also added PPMd var I to the MFC test.
22-November-2005 : Added 7-zip 4.30b, LZPX 1.6pre1, SRANK 1.0 and Squeez 5.10. LZPX shows spectacular compression improvements compared to LZPX 1.5b (it now takes place #30 in SFC), but compression speed was also badly affected. 7-Zip 4.30b is similar to latest alpha 9 version, Squeez doesn't show any changes compared to 5.0.
14-November-2005 : Added UHarc 0.6b, 7-zip 4.30a9, WinZIP 10.0, WinHKI 1.58, LZPX 1.5a and HIPP 0.5819. Uharc, WinZIP and WinHKI have the same compression as previous version, LZPX has improved compression, 7-Zip 4.30 alpha 9 has better compression in Ultra mode and is also (much) faster!. HIPP is a new piece of compression software with great results on the SFC testset, taking 10th place in best overall compression program, method 2. All programs (except HIPP which crashes when using the /m switch to reduce memory usage) are also added to MFC. I'm still busy getting the best SFC switch combinations for 7-Zip 4.30a9, if someone finds a better switch combination then the one currently listed please let me know. Update: Improved 7-Zip switch setting for the EXE and HLP test (thanks to Mauro Vezzosi).
07-November-2005 : Added KZIP 05-11-2005 and PPMZ2 0.81. Again found a better 7-Zip switch setting for the DICT, TXT and HLP (thanks to Mauro Vezzosi) and DLL (thanks to Vidmantas Balciunas) test. PPMZ2 0.81 crashes on the MFC test after compressing about 64 Mb (out of memory?).
31-October-2005 : Added LZPX 1.4m and M03; Due to the -d switch LZPX shows improved compression in JPG, PDF and DOC test. M03 takes place #40 in SFC. Found a better 7-Zip switch setting for the DICT test (thanks to Guillermo Gabrielli). Added ACB 2.00c to the MFC test, Emilcont 0.3a crashes on the same MFC test.
17-October-2005 : Added LZPX 1.4a, WinRAR 3.51, 7-ZIP 4.30a, PAsQDa 4.1b, ARJ 2.84/ARJ32 3.14 and WinHKI 1.57 to both SFC and MFC; LZPX has better compression then previous versions, but is slower. No changes for WinRAR, 7-ZIP, ARJ, WinHKI and PAsQDa. Update 24-Oct: Added LZPX 1.4f; LZPX has (again) better compression then previous version, and it's also a bit faster.
01-October-2005 : Added 7-Zip 4.29, TC 4.3, and BEE 0.7.8. Finally a new version of BEE has arrived; version 0.7.8 build 0154. It has greatly improved compression compared to 0.7.7 on most of the single file tests especially DICT (-350 Kb!!), PDF (-74 Kb) and BMP (-43 Kb). It now moved to place #14 in SFC. Strangely it shows hardly any improvements on the MFC-testset (about -300 Kb).
23-September-2005 : Added BMA 1.31, 7-Zip 4.27, LZPX 1.2 and LZOP 1.02rc1. BMA 1.31, has improved compression for almost all testfiles (now taking 36th place in SFC test).
05-September-2005 : Added WinZip 10.0b, BMA 1.30, TC 4.2, ALZip 6.1, LZPX 1.1 and MAr (Melting-Pot Archiver). The new PPMd mode in WinZip 10 greatly enhances compression, in SFC it now climbs to place 40 compared to WinZip 9.0 which took place 92. It seems WinZip 10 uses PPMdI (PPMD-2002) with -mem50m -o8 settings by default when selecting the new PPMd mode. BMA 1.30 has better compression compared to version 1.27 (taking 38th place) and is faster (a rare combination). For an overview of the single file compression results have a look at the summary pages. All six programs are also added to MFC, the results can be viewed sorted on size, efficiency and compression time.
27-August-2005 : Made some changes to the layout of the multiple and single file summary pages. On the MFC pages it's now possible to sort the data on compression ratio, time and efficiency. Added (additional) entries in MFC for AIN 2.32, HPACK 0.79a, GZIP 1.2.4, HYPER 2.5, DACT 0.8.39, RZIP 2.0, MS CABARC and LZPX 1.0f.
21-August-2005 :
SFC : Added WinACE 2.6, Kzip 17-08-2005, UPX 1.93w and WinHKI 1.56 (no changes compared to their previous versions).
MFC : Added ZZIP 0.36c, WINIMP 1.21, UHBC 1.0, BA 1.01 and PPMN 1.00b1 km. Added some additional entries (with different switches) for YBS 0.03f, DC 0.99.307b and PAQAR 4.0.
14-August-2005 :
SFC : Added WinRK 2.1.6, Kzip 03-08-2005, Lz2a, WinRAR 3.50 and 7-Zip 4.26. Compression ratio of WinRK 2.1 build 6 is almost identical to build 4, so WinRK still takes first place in the Single File Compression testset.
MFC : Added WinRK 2.1.6, Durilca light 0.4b, Kzip 03-08-2005, WinUDA 0.291 and Lz2a. Durilca light scores very well on the efficiency scale, taking a 2nd place. The archive size of WinRK 2.1.6 'FAST' method was almost 2 Mb larger, but the speed was improved with 35%. As with SFC, WinRK 2.1.6 in PWCM mode, still takes first place on compression ratio. Also added some additional entries (with different compression settings) for Uharc 0.6a, Slim 0.23, WinACE 2.5, PPMonstr rev I, UFA 0.04b1 and 777 0.04b1.
01-August-2005 : Added BioArc 1.9, MBA 1.27 and Quark 0.93 (Quark takes 21th place in SFC testset). Added 7-Zip 4.24, WinRK 2.1.4, PAsQDa 4.1, BioArc 1.9, BMA 1.27 and Quark 0.93 to the multiple file compression (MFC) results. Here, just like in SFC, WinRK 2.1.4 takes first and PAsQDa 4.1 takes second place on compression ratio. The new FPW (Fast Paq Weighting) algoritm in WinRK also boosts the efficiency score of WinRK. For an overview of the MFC results have a look at the summary pages; ranked on compression ratio and efficiency.
14-July-2005 : Added 7-Zip 4.24b, WinHKI 1.54, WinRAR 3.50b7 and SBC 0.970 rev2 (no changes compared to previous versions). Tested PAsQDa 4.1, this latest version of the PAQ family shows a nice improvement in the TEXT-file test (-6 Kb). Overall PAsQDa still takes 2nd place in the single file compression testset. Tested WinRK 2.1 build 4; apart from many bug fixes, the biggest news is the improvements made to the PWCM codec plugin. The speed is improved and some extra models were added along with some modifications to the text filtering. This method now compresses significantly better, especially on the text data and bitmap test; TXT (-8 Kb), LOG (-11 Kb) and BMP (-7 Kb). Some degradation was seen in the HLP (+6 Kb) and DICT (+4 Kb) test. WinRK 2.1.4 now takes 5 1st places, PAsQDa 4.1 takes 4 1st places. For an overview of the single file compression results have a look at the summary pages. Results of the multiple files testset will be added later on.
15-June-2005: Added WinRK 2.1 build 1. As this release was mainly aiming for improved stability, compression ratios are about the same as previous version. So WinRK (using PWCM) is still number one in the single file compression testset. While testing the multiple files testset it was clear the stability was improved (it now passes the test using PWCM, which failed in all previous versions). WinRK's PWCM now takes first place in the multiple file compression test ranked on compression rate. For a high score in efficiency it's obvious to slow, but who cares :)
02-June-2005 : Updated 7-Zip 4.19b to 7-Zip 4.20, WinHKI 1.52 to WinHKI 1.53, WinRAR 3.50b4 to WinRAR 3.50b5 (no changes) and TC 4.0b to TC 4.1 (small improvements of a few bytes to about 1.5 Kb). Added Chaos Compressor 3.0 and DeepFreezer 1.06.
23-May-2005 : Updated 7-Zip 4.18b to 7-Zip 4.19b, BZip2 1.0 to BZip2 1.0.3 (no changes) and TC 3.6 to TC 4.0b (some big improvements on some files; DOC, DLL, LOG, TXT and big losses on other ones; JPG, PDF, DICT). In the multiple file compression section there now is a ranking based on efficiency of the compressors (please note there is still a lot of work to do here, like testing other programs, improving layout etc...).
11-May-2005 : Updated WinRAR 3.50 b3 to WinRAR 3.50b4 (no changes) and TC 3.5 to TC 3.6 (some big improvements on the hard to compress files; PDF and JPG). Still playing around with Squeez 5.0 beta 3, and still getting different results on the command-line compared to the GUI.
30-April-2005 : Updated WinHKI 1.51 to WinHKI 1.52. No changes. Added Squeez 5 beta 2. While testing I noticed Squeez 5 seems to get better compression results using the command line in stead of the GUI (with it's many partly hidden features, like text, multimedia, audio and ultra mode compression). If someone is ably to get better results (especially when using the GUI) then the ones currently listed please let me know!.

Update : Improved compression settings for TXT, LOG, BMP, DOC, DLL and EXE test (thanks to Stephan Busch and Sven Ritter). Squeez moved up to 14th place in best overall compression program, method 2. The problem with different compression sizes in GUI and command-line is caused by a bug in the beta 2 version of the program. This will hopefully be solved in the final version.
23-April-2005 : Updated 7-Zip 4.16b to 4.18b, WinRAR 3.50b2 to WinRAR 3.50b3, DGCA 1.07 to DGCA 1.08, BCArchive 1.03 to BCArchive 1.04. No changes.
09-April-2005 : Updated 7-Zip 4.15b to 4.16b, WinHKI 1.4g to WinHKI 1.51, WinRK 2.0 build 5 to build 6, ALZip 5.5 to ALZip 6.03b and WinRAR 3.42 to WinRAR 3.50b2. All mentioned programs show no changes in compression size. Updated TC 3.3 to TC 3.5 (improvements in all 10 tests) and tested the latest PAQ family members called PAsQDa 4.0 and PASQDA 3.9 (Version 3.9 is PASQDA 4.0 but with reduced memory usage, making it possible to use -8 option on computers with 1GB memory). Version 3.9 has improved compared to 3.0, especially in the TXT-test (now taking first place away from WinRK). PASQDA 3.9 is ranked number two in best overall compression program, both method 1 and 2.
19-March-2005 : Added TC 3.1 and StuffIt 9.0 beta, updated BSSC 0.93a to BSSC 0.95a (all 10 tests show small improvements). The latest StuffIt version (build 9.0.0.21) now contains the JPG compression algorithm tested earlier (see the 12 January update). It compressed the a10.jpg test-file from 842468 to 638518 bytes (that's 24%), taking first place in the JPG test with a BIG margin. Combined with a good improvement on the dictionary test and other tests being on par with version 8.5, this results in a 14th place in best overall compression program, method 2.
06-March-2005 : Added 2 new programs; 12Ghosts 7.0 and BSSC 0.93 alpha, and updated WinACE 2.6b4 to WinACE 2.6b5 (no changes).
22-February-2005 : Added GZip 1.3.5, BCArchive 1.03 and SHCodec 1.01. BCArchive has identical compression compared to version 1.02.2, GZip on average compresses slightly worse then v1.2.4. The first preliminary results of the multiple file compression tests are online. It will probably take months to complete the testing, but I promise new results will be added to this page on a regular basis.
13-February-2005 : Tested PAsQDa 3.0 (basically it's PAQAR4.0 with an external dictionary). It now has slightly better results then the previously best PAQ family member (PAQAR 4.0). The difference is just 600 bytes. Normally I would remove PAQAR 4.0 from the database and replace it by PASQDA, but I'm a bit reluctant to do so because PAQAR carries a lot of history. I think I will keep PAQAR in the results of the seperate tests but exclude it from the 'best overall compression program' scores. Will have to think a little more about it.

I finally started with the multiple file compression tests. I will not test the Calgary corpus set as other sites already do an excellent job at that. I designed my own testset containing several hundred files totaling 300+ Mb. A sneak preview can be found here.
02-February-2005 : Updated 7-Zip 4.14b to 4.15b, and WinRK 2.0 build 4 to build 5 (no changes). Tested the latest PAQ family member called PAsQDa 2.1; it's basically PAQAR4.0 with added WRT preprocessor/dictionary. It got slightly better results compared to PAQAR 4.0 in the TXT and LOG test, but because I wasn't able to run PAsQDa in -8 memory mode (heavy disk trashing) the compressed size was slightly larger then with PAQAR 4.0. The difference between the two is just 461 bytes(!).
21-January-2005 : Added WinRK 2.0 build 4. First I tested the normal PPMZ algorithm, it has greatly improved on the LOG file (-26 Kb) but is totally lost on the DICT-file (+168 Kb). Next I tested PWCM (PAQ Weighted Context Model) algorithm; it now surpasses PPMZ in all 10 tests!. WinRK's PWCM now takes first place in 8 out of 10 tests (EXE,DLL,TXT,BMP,JPG,PDF,HLP,DICT) and second in the 2 remaining (LOG,DOC)!. It's no surprise WinRK 2.0.4 is still ranked number one in best overall compression program, both method 1 and 2 (and the gap to number 2 is getting bigger).
12-January-2005 : Updated 7-Zip 4.13b to 4.14b (no changes).
Last week I was one of the lucky people to receive a test application from allume (known from the Stuffit compressor), to verify/test a new compression algorithm that will losslessly compress JPG/JPEG files by as much as 20-30%. This is *much* higher then current compression software is capable of. The test application compressed the a10.jpg test-file from 842468 to 643403 bytes (that's almost 24%). The results will be added to the database after the release of Stuffit 9 (which will include the new algorithm).

Previous updates - 2004

31-December-2004 : Added PKZip 2.50, WinRAR 3.42, WinHKI 1.4e and WinAce 2.6b4. WinRAR, WinHKI and WinACE have identical compression as their previous versions. The best overall compression program, method 2, now shows the best 35 entries (instead of just 20). It's also possible to download the complete list (115 entries) in zip-file format.
20-December-2004 : Added UHarc 0.6. The latest UHarc version has improved compression in all 10 tests, compared to previous (non-public) 0.5, which was already better then previous public version 0.4. Uharc 0.6 takes 12th place in best overall compression program, method 2. Uharc is especially suited for compressing large file-sets with a good compression ratio and speed.
19-December-2004 : Added WinRK 2.0 build 1. The latest WinRK version includes a new experimental compression algorithm called PWCM (PAQ Weighted Context Model), based on PAQ's context modelling ideas, but with some additional features such as image compression and other filtering techniques. Testing the good old PPMZ algorithm gave about the same results as previous WinRK. The PWCM compression method however rocks big time, it's slightly faster as PAQAR, but in most cases compresses better. WinRK 2.0 takes first (EXE,DLL,TXT,BMP,JPG,PDF) or second (HLP,DICT,LOG,DOC) place in ALL tests!. It's now ranked number one in best overall compression program, both method 1 and 2. Well done, Malcolm!!.
28-November-2004 : Added 7-Zip 4.12b and Rzip 2.0. 7-Zip 4.12b has exactly the same compression as previously tested 7-Zip 4.09b.
02-November-2004 : Added Ocamyd 1.64, WinRAR 1.41, WinHKI 1.4c, BCArchive 1.02.1 and WinAce 2.6b3. Compression of Ocamyd 1.64 has improved in all tests compared to v1.63. WinRAR 1.41, WinHKI 1.4c, BCArchive 1.02.1 and WinAce 2.6b3 have exactly the same compression as their previous versions; WinRAR 1.40, WinHKI 1.4b, BCArchive 1.02 and WinAce 2.6b2 respectively.
17-October-2004 : Added ALZip 5.5; compression in JPG and PDF test is slightly worse then with version 5.2.
06-October-2004 : Added Ocamyd 1.63, WinHKI 1.4b, Slim 0.23d, 7-Zip 4.09b, DGCA 1.06 and WinAce 2.6 beta 2. Compression of Ocamyd 1.63 is almost identical to 1.62 except for the BMP test, which is a few Kb smaller. Slim 0.23d, 7-Zip 4.09b, WinHKI 1.4b, DGCA 1.06 and WinAce 2.6b2 have exactly the same compression as their previous version, Slim 0.23c, 7-Zip 3.13, WinHKI 1.4, DGCA 1.05 and WinAce 2.6b1 respectively.
26-September-2004 : Added Ocamyd 1.62 and Durilca 0.4b. Ocamyd 1.62 is identical to 1.60 except for the BMP test which is about 0,5 Kb larger. Durilca 0.4b outperforms Durilca 0.4a in every test except JPG, PDF and DOC. It now takes 2nd position in both best overall compression program, method 1 and 2, behind PAQAR. It also claims first place in both EXE and DLL compression test.
23-September-2004 : Added BCArchive 1.01b and Ocamyd 1.60 from Frank Schwellinger, the man who releases new versions faster then I can test. :) Ocamyd 1.60 has similar compression compared to v1.58 (+/- a few bytes) except for the BMP test where it gains 9 Kb thanks to the new image compression algorithm. BCArchive 1.01b is identical to BCArchive 1.00b.
18-September-2004 : Added WinHKI 1.4, DGCA 1.05, WinRAR 3.40 final and Ocamyd 1.58; Ocamyd 1.58 has similar compression compared to v1.57 (+/- a few bytes). The final WinRAR 3.40 has exactly the same compression as the latest Beta's. WinHKI 1.4 compression is the same as version 1.3g, DGCA 1.05 same as DGCA 1.04.
07-September-2004 : Added Ocamyd 1.57 and Slim! 0.23c. This latest Slim! version has a bugfix (which doesn't affect compression ratio compared to 0.23). Ocamyd 1.57 has also a bugfix and a new switch, especially improving the LOG-file compression. On most other files there are very small improvements or very small losses. Ocamyd still takes 11th place in best overall compression program, method 2.
31-August-2004 : Added SLIM! 0.23 and DGCA 1.04. In comparison to 0.22 this new version of SLIM! has improved SSE modeling and weighing and also an improved EOL coder. Compared to last version it has minor improvements in all tests except the BMP test. SLIM 0.23 takes 2nd place in HLP, LOG, DLL and 3th place in DICT, EXE, DOC and PDF compression, resulting in a 3th place in best overall compression program, method 1 and a 2nd place in best overall compression program, method 2!.
26-August-2004 : Added WinHKI 1.3g and WinRK 1.1 (build 3). Compared to WinRK 1.1.2, version 1.1.3 shows a big improvement in the TXT test (now taking 3th place), and a nice improvement in the DLL test. WinRK takes first place in PDF and JPEG compression, 2nd place in DICT and 3th in DOC, TXT. It still takes 4th place in best overall compression program, both method 1 and 2.
21-August-2004 : Added WinRAR 3.40b5 and WinRK 1.1 (build 2). The compression ratios of WinRK 1.1 and 1.0 are about the same except for the DOC and TXT test. The compressed size of the DOC file is 9 Kb smaller (WinRK 1.1 takes 3th place here), the compressed TEXT file is 20 Kb bigger. WinRK takes first place in PDF and JPEG compression, 2nd place in DICT and 3th in DOC. It takes 4th place in best overall compression program, both method 1 and 2.
17-August-2004 : Added Ocamyd 1.56, included a mini FAQ on the Summary page and added some more historic data (older versions of ASH, EPM and BEE) to the database. Ocamyd 1.56 again shows improvements for all tests in the Maximum Compression benchmark, both because of improved compression algorithms and by the addition of a switch to select the best compression variant. Ocamyd now takes 11th place in best overall compression program, method 2.
10-August-2004 : Added WinRAR 3.40b4 and Ocamyd 1.55 Markov Edition 912 version 1 (which scored slightly better then 1.55 ME912 version 2). This ocamyd version again shows improvements for all tests in the Maximum Compression benchmark, biggest gains are in EXE and DLL test. Ocamyd 1.55 ME912 now takes 12th place in best overall compression program, method 2.
06-August-2004 : Added an option on every page named 'Show historic data'. After clicking this link the page will be reloaded, now including historic data (name + size of previous compressor version) in 3 extra columns. This data will be filled as new versions arise. A shortcut to get to this addition data is adding '?historic=true' after the URL. For example the DOC-test: (http://www.maximumcompression.com/data/doc.php?historic=true). Navigation between the different tests is also made easier by adding navigation buttons on the lower right part of the screen. Finally the number of compressors tested per test is now indicated.
27-July-2004 : Added PAQAR 4.0, UPX 1.92w and WinRAR 3.40b3. PAQAR 4.0 again has improved compression and decreased speed compared to previous 3.0 version (to give you an idea, on my AMD 2800+ Barton it now compresses with 5 Kb/s). Improvements can be seen in EXE, DLL, HLP and TXT test (in the TXT test it now takes 1st place, making 6 1st places in total!). It will be no surprise PAQAR (4.0) is still ranked number one in best overall compression program, both method 1 and 2.
17-July-2004 : Added Ocamyd 1.54 Markov Edition 912. The Markov Editions are enhanced versions of Ocamyd v1.54 allowing for memory usage up to 912 MB. This boosted version shows big improvements for all tests in the Maximum Compression benchmark except the PDF test. PDF compression is still slightly worse then with (normal) version 1.51/1.52. Ocamyd 1.54 ME912 now takes 13th place in best overall compression program, method 2.
13-July-2004 : Added PAQAR 3.0, Durilca 0.4a, Ocamyd 1.53 and WinHKI 1.3f. PAQAR 3.0 again has improved compression compared to previous 2.0 version. Biggest improvements are in LOG and TXT test (in the TXT test it now takes 2nd place). Needless to say PAQAR (3.0) is still ranked number one in best overall compression program, both method 1 and 2. It's still the best, but Durilca is slowly closing the gap...

Durilca 0.4a outperforms Durilca 0.4 in every test except JPG, taking 2nd position in both best overall compression program, method 1 and 2 away from SLIM 0.22. It also claims first place in DLL compression test. Ocamyd 1.53 shows (large) improvement in all tests except DICT and PDF, now taking 14th place in best overall compression program, method 2.
06-July-2004 : Added SLIM 0.22, WinRAR 3.40b2 and UPX 1.91. SLIM has switched from PPM* to PPMII and has improved sse data modelling. Compared to last version it has (greatly) improved compression in all tests except the hard to compress filetypes (JPEG and PDF test). SLIM 0.22 takes 1st place in DLL, 2nd in HLP, LOG and 3th in DICT, DOC, EXE, PDF compression, resulting in a 2nd place in best overall compression program, method 1 and also a 2nd place in best overall compression program, method 2. Well done Serge!.
30-June-2004 : Added Archiver 1.0 and Ocamyd 1.52. This version of Ocamyd has improved hugely on the dictionary and logfile test, but loses a bit in most other tests (compared to previous 1.51 version). It takes 2nd place in the jpeg test and 17th place in best overall compression program, method 2.
24-June-2004 : Added PAQAR 2.0, WinACE 2.6b1 and Ocamyd 1.51. WinACE 2.6b1 doesn't improve on compression compared to last 2.5 version. Ocamyd has improved compression compared to the previous version on most files, but the EXE-file compresses much worse. PAQAR 2.0 again has improved compression for all 10 test-files compared to version 1.3. It still takes 1st place in best overall compression program, both method 1 and 2. It scores a top 3 position in all 10 tests!!.
21-June-2004 : Added Ocamyd 1.50 and WinRAR 3.40 beta 1. Ocamyd takes 2nd place in the jpeg compression test and 19th place in best overall compression program, method 2. WinRAR is still on place 16.
09-June-2004 : Added PAQAR 1.3. The best even got better, this version has improved compression for all 10 test-files compared to version 1.2. PAQAR is without a doubt the worlds best compression program at this moment!. It takes 1st place in best overall compression program, both method 1 and 2. Moreover it now scores a top 3 position in all 10 tests!!.
23-May-2004 : Added PAQAR 1.2 (Greatly improved PAQ6 variant by Alexander Ratushnyak; more information about this program can be found on Matt Mahoney's site). This program is memory hungry (920 Mb using the -8 switch) and slow (on my AMD 2800+ Barton it compresses with a speed of 7 Kb/s), but if you want the best possible compression this is it!. It takes 1st place in best overall compression program, both method 1 and 2. Moreover it scores a top 4 position in all 10 tests!!. As many people already expected, PAQ reached #1.
14-May-2004 : Added GRZipII 0.2.4, WinHKI 1.3e and WinRK 1.0 final (build 5). The compression ratios of the final WinRK version are slightly worse then the last beta. It still takes first place in PDF and JPEG compression, 2nd place in DICT and TXT, 3th in DLL. It takes 3th place in best overall compression program, method 1 and 4th place in best overall compression program, method 2 (losing a place to PAQ6 EH in both rankings).
04-May-2004 : Added PAC (ver 17apr2004) and BCArchive 1.00b. Tested PAQ6-Emilcont-Italia: PAQ6-EI has similar compression compared to PAQ6-Harlock for all filetypes, but uses a bit more memory.
18-April-2004 : Added WinHKI 1.3d, Stuffit 8.5, BAR 1.1.2, DACT 0.8.39 and PAQ6-Emilcont-Harlock. PAQ6-EH has improved compression compared to PAQ6-Emilcont-Blaster/Destroyer/ Annyhilator for every filetype except the LOG-file which increases by 20 Kb. Also made some cosmetic changes to the site.

Tested PAQ6ed-schmidtvarA and PAQ6ed-schmidtvarB. Both programs showed similar compression, mainly because I wasn't able to run varB versions in -8 (memory) mode (even with all background progs disabled). Compared to PAQ6-Emilcont-Harlock they show sligthly better compression for BMP and TXT, but worse compression for the other file types. Overall PAQ6-EH is still the better compressor for my testset.
08-April-2004 : Added PAQ6-Emilcont-Blaster. PAQ6-EB has improved compression compared to PAQ6-EA on all filetypes.
02-April-2004 : Added Dulica 0.4 and PAQ607fb-Emilcont-Anny (a merged version of PAQ6-EA and PAQ607fb). PAQ607fb-EA takes 1st place in HLP, DICT and 2nd in BMP, PDF compression. It also takes 3th place in best overall compression program, method 1 and 4th place in best overall compression program, method 2. PAQ6 is aiming for the number 1 position!. Durilca 0.4 has improved compression compared to version 0.3a on all filetypes and takes 1st place in EXE, DLL, DOC and LOG compression. It also takes 1st place in both 'best overall compression program' method 1 and 2. Good job Dmitry!.
30-March-2004 : Added DACT 0.8.37, DZIP 2.9, ALZip 5.2 and PAQ6-Emilcont-Anny. PAQ6-EA has improved compression compared to PAQ606fb on all filetypes tested except JPG (where it gains a few bytes...). This version now takes 1st place in HLP and 2nd place in BMP, PDF and DICT compression. It also takes 3th place in best overall compression program, method 1 and 5th place in best overall compression program, method 2!. Also tested PAQ6 607fb, but this version seems to be optimized especially for the Calgary Corpus testset. Compression the MC test-files results in worse compression for most filetypes.

The site now contains an other benchmarks section. This section has links to other benchmarks sites and spreadsheet with testresults from other testers. Improved the Test Files page: It's now possible to download all used testfiles in one package.
25-March-2004 : Added SBC 0.970 and WinHKI 1.3c.
18-March-2004 : Added WinHKI 1.3b, PAQ606fb and WinRK 1.00b2. PAQ 606fb is less memory hungry then PAQ6fbj8-9 so I was able to run it in -8 memory mode. Total size off all 10 compressed files is a bit lower then the previous version. This version takes 5th place in both best overall compression program, method 1 and 2). WinRK 1.00 beta 2 takes first place in PDF, JPEG and DICT compression, 2nd place in DOC and TXT, 3th in DLL. It now takes 1st place in best overall compression program, method 1 and 2nd place in best overall compression program, method 2. Congratulations Malcolm!!.
09-March-2004 : Added PSA 0.91a and WinHKI 1.3 (version 1.3 supports many new compression formats like CAB/GZIP/JAR/LHA, but only the 'native' HKI algoritms are used here).
24-February-2004 : Added WinZIP 9.0 final and WinHKI 1.2g.
14-February-2004 : The programs page now indicates if a compressor has a build in or external/third party GUI. Added ICEOWS 4.20b, WinHKI 1.2f, DCA 1.0.1b, LHA32 1.88.3.14 and the long awaited WinRK 1.00b1. This program is an enhanced RKC version with nice GUI. The test results were rather surprising; It takes first place in JPEG and PDF compression without a problem, but loses ground to RKC on DLL, EXE, DOC, DICT and BMP compression (according to the readme file, the EXE format compression, and the image specific compression should be solved in the next release). Also tested PAQ6fbj8 and PAQ6fbj9, both programs showed similar compression compared to PAQ605fbj. The algoritms are probably a bit better, but because I wasn't able to run these versions in -8 (memory) mode, results are not much better.
30-January-2004 : And again a new PAQ6 version (PAQ605fbj). It has a new recordmodel, changes to state tables and includes the CACM coder. This results in improved compression (compared to PAQ6 fdj) for all filetypes except jpg.
26-January-2004 : Again a new PAQ6 version (PAQ603) and again improved compression (compared to PAQ6 fdj) for most filetypes. EXE and DLL test both improve with well over 5 Kb, dictionary test with 15 Kb. The 'old' PAQ6 version was already holding the #1 position in the HLP-test, this version improves it with 4Kb!. Added WinRAR 3.30 final.
20-January-2004 : Added PAQ6 fdj, this is an improved (and faster) version of the PAQ6 program, using 64 bit arithmetic encoding and modifications to the mixer and matchModel. It has improved compression for most filetypes, but doesn't gain any positions in 'best overall compression program', method 1 and 2.
09-January-2004 : Added JCALG1 5.32 and WinRar 3.30b5. On the Compression Programs page added two columns to indicate if a compressor has a build in (or external) GUI and the algorithms used (if known) by that program.

Previous updates - 2003

31-December-2003 : Added PAQ6 (this version of the PAQ program, with excellent documented source code available, has improved compression for all filetypes and now takes 1st place in HLP and PDF compression. PAQ6 takes 4th place in both best overall compression program, method 1 and method 2) and SLIM 0021 (this new version has small compression improvements for some filetypes and takes 1st place in EXE and DLL compression. SLIM0021 now takes 3th place in best overall compression program, method 1 and 1st place in best overall compression program, method 2. Congratulations Serge!!).
26-December-2003 : Added SLIM 0020 (this version has improved compression for all filetypes except jpeg and now takes 3th place in best overall compression program, method 1 and 2th place in best overall compression program, method 2 - just 700 bytes from the #1 position).
19-December-2003 : Added PAQ5 (takes 4th place in best overall compression program, method 1 and 5th place in best overall compression program, method 2) and WinRar 3.30b4.
10-December-2003 : Added WinRar 3.30b3, GRZipII 0.2.3 and 7-Zip 3.13.
05-December-2003 : Added SLIM 0019 (no difference in compression compared to version 0018 of this compressor) and ASH 04a (little improvement in compression compared to version 04 of this program).
29-November-2003 : Added BJWFLATE 1.54 and retested 7-zip 3.11 (small improvements for JPG, PDF, HLP and DOC-tests; special thanks to Taylor Smith).
25-November-2003 : Added ASH 04 (has improved compression for all 10 test files compared to version 03; takes 8th place in best overall compression program), AVID 0.6b and WinRar 3.30b2. Removed 'PC mem' column as all compressors are now tested with optimal memory configuration, also added a 2nd 'Best overall compression program' scoring system. The compressed size of all 10 tests per program are added up. The program with the lowest total is considered the best program.
10-November-2003 : Added BEE 0.7.7b, DST 0.91b and WinRar 3.30b1
03-November-2003 : Added ASH 03 (has improved compression for all 10 test files compared to version 02; takes 8th place in best overall compression program), GRZipII 0.2.2, ARJ 2.82b1, Transform 1.02 and ShipInBottle 1.0 beta 16.
26-October-2003 : Added SLIM 0018 (Version 0018 has improved compression for all 10 test files compared to version 0017!; the program will take 3th place in best overall compression program), Durilca 0.3a (some good improvements for EXE and DLL test, little degradation in other tests; takes 1st place in best overall compression program!) and PPMY SSE 9A9 (some spectacular improvements for LOG and DICT test). Retested RK 1.04.1 (small improvements for EXE and DLL test). Investigated KTY 0.04; as it seems a 1:1 PAQ4 clone, this program will not be added. Again changed the point system for 'best overall compression program'. I really think this is the final version (...).
19-October-2003 : Added EPM r9 (2nd in DOC,HLP,DICT,LOG and PDF test; 3th in DLL and EXE test; 4th in BMP test; 5th in TXT test; 1st place in best overall compression program!), SLIM 0017 (1st in DLL,HLP test; 2nd in EXE test; 3th in PDF test; 4th in DOC,LOG and TXT test; 5th in DICT test; 3th place in best overall compression program), PAQ4 and PAQ4 Ultra (recompiled version of PAQ4 supporting 700 Mb of memory; 1st in PDF test; 2nd in JPG and BMP test; 3th in HLP test; 4th place in best overall compression program). Also added a guestbook where you can post your improvement tips, ideas etc.
09-October-2003 : Added 7-zip 3.11, PAQ3n and PAQ3n Ultra (recompiled version of PAQ3n supporting 512 Mb of memory). Changed 'best overall compression program' criteria/ranking in summary page.
05-October-2003 : Added CTXf 0.75 b1, 7-Zip 3.10, KZip and PAQ3 Ultra (recompiled version of PAQ3 supporting 1 Gb memory). Retested the following programs on the new 1024 Mb memory machine: Durilca 0.2, SLIM 0016, RKC 1.02, EPM r8, 7-Zip 3.10, ASH 02, PPMonstr, Kzip, ENC 0.15, BEE 0.7.6d, PPMY SSE (9A8). Results will be marked with '1024' when run on the new PC and '512' for the old one. If you know of a (top)program capable of using more then ~450 Mb which is still marked '512' please let me know!.
16-September-2003 : Added RKC 1.02 (takes 1st place in TXT test, 2nd place in DLL, EXE and DOC test : combined 2nd in best overal compression program), Epm r8 (takes 1st place in PDF test, 2nd place in HLP and LOG test, 3th in DOC and BMP test : combined 2nd in best overal compression program), SLIM 0016 (takes 1st place in HLP test, 2nd place in PDF test, 3th in DLL and EXE test : 4th in best overal compression program), PAQ3 and 7-Zip 3.09.01. Retested Durilca 0.2 (small improvements for EXE, DLL, HLP and DOC-tests).
29-January-2003 : Day one of MaximumCompression :-)