Dojo 1.7.0 - as small as it gets (near-perfect GZIP compression)

Choose a version:

The original file has 477240 bytes (466.1k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 117915 bytes (115.2k, 25%).

After GZIP compression these minified files vary in size:

Boot	47178 bytes (46.1k)	CDN
Yandex	45164 bytes (44.1k)	CDN
Baidu	40986 bytes (40.0k)	CDN
cdnjs	40979 bytes (40.0k)	CDN
gzip -6 (default)	40838 bytes (39.9k)	local copy
gzip -9	40818 bytes (39.9k)	local copy
7zip -mx=9 -tgzip	38948 bytes (38.0k)	local copy
libdeflate -12	38915 bytes (38.0k)	local copy
kzip -s0 -rn -b1	38913 bytes (38.0k)	local copy
zultra	38879 bytes (38.0k)	local copy
pigz -11 -n	38856 bytes (37.9k)	local copy
Zopfli	38806 bytes (37.9k)	local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/dojo/dojo-1.7.0.min.js (or via HTTPS)

You will automatically get the smallest Dojo 1.7.0 file, ETag caching is available and
if your browser doesn't support GZIP decompression then the uncompressed version will be sent.

Currently best Zopfli settings

Save 2173 bytes by using my Dojo 1.7.0 Zopfli version instead of the best available CDN (5.60% smaller than cdnjs, 38806 vs. 40979 bytes):

Download

You can use my super-compressed files for whatever purpose you like as long as you respect the library's original license agreement.
There are no restrictions from my side - but please avoid hot-linking if you run a high-traffic website.

These command-line settings yielded the best compression ratio so far (Linux version of zopfli-krzymod):
zopfli --i1000000 --mb8 --mls16384 --bsr25 --lazy --ohh

(found February 26, 2020)

Description	Value	Parameter
iterations	1000000	--i1000000
maximum blocks	8	--mb8
maximum length score	16384	--mls16384
block splitting recursion	25	--bsr25
lazy matching in LZ77	yes	--lazy
optimized Huffman headers	yes	--ohh
initial random W for iterations	1	--rw1
initial random Z for iterations	2	--rz2

Verify file integrity

After decompression, my uncompressed files are identical to the original ones:

MD5:
curl --silent --compressed https://download.dojotoolkit.org/release-1.7.0/dojo.js --location | md5sum
9c61a9c6197d50003424553add886f70 -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.7.0.min.zopfli.js.gz | md5sum
9c61a9c6197d50003424553add886f70 -

SHA1:
curl --silent --compressed https://download.dojotoolkit.org/release-1.7.0/dojo.js --location | sha1sum
e2dc7a9185cb76b9f4a805e1fd7417627dce425d -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.7.0.min.zopfli.js.gz | sha1sum
e2dc7a9185cb76b9f4a805e1fd7417627dce425d -

These CDNs send you the original file:

CDN	Size (compressed)	MD5 (uncompressed)	Timestamp
Boot	47178 bytes	9c61a9c6197d50003424553add886f70	March 19, 2015 @ 15:33
cdnjs	40979 bytes	9c61a9c6197d50003424553add886f70	February 8, 2015 @ 14:45

And some CDNs send you a different file:

CDN	Size (compressed)	MD5 (uncompressed)	Comment / Diff	Timestamp
Yandex	45164 bytes	49fb00782551c5b6dcac070ce016c862	< (function(_1,_2){var _3=function(){},_4=function(it){for(v [...] > (function(_1,_2){var _3=function(){},_4=function(it){for(v [...]	June 20, 2013 @ 11:59
Baidu	40986 bytes	4d3f67aadbfb615cedb955d43c7d9c0b	only whitespaces differ	January 7, 2015 @ 10:16

Note: only the MD5 hashes are shown to keep things simple.

Other Versions

Available Dojo versions at minime.stephan-brumme.com:

1.17.3, 1.17.2, 1.17.1, 1.17.0,
1.16.5, 1.16.4, 1.16.3, 1.16.2, 1.16.1, 1.16.0,
1.15.6, 1.15.5, 1.15.4, 1.15.3, 1.15.2, 1.15.1, 1.15.0,
1.14.9, 1.14.8, 1.14.7, 1.14.6, 1.14.5, 1.14.4, 1.14.3, 1.14.2, 1.14.1, 1.14.0,
1.13.10, 1.13.9, 1.13.8, 1.13.7, 1.13.6, 1.13.5, 1.13.4, 1.13.3, 1.13.2, 1.13.1, 1.13.0,
1.12.11, 1.12.10, 1.12.9, 1.12.8, 1.12.7, 1.12.6, 1.12.5, 1.12.4, 1.12.3, 1.12.2, 1.12.1,
1.11.13, 1.11.12, 1.11.11, 1.11.10, 1.11.9, 1.11.8, 1.11.7, 1.11.6, 1.11.5, 1.11.4, 1.11.3, 1.11.2, 1.11.1, 1.11.0,
1.10.10, 1.10.9, 1.10.8, 1.10.7, 1.10.6, 1.10.5, 1.10.4, 1.10.3, 1.10.2, 1.10.1, 1.10.0,
1.9.11, 1.9.10, 1.9.9, 1.9.8, 1.9.7, 1.9.6, 1.9.5, 1.9.4, 1.9.3, 1.9.2, 1.9.1, 1.9.0,
1.8.14, 1.8.13, 1.8.12, 1.8.11, 1.8.10, 1.8.9, 1.8.8, 1.8.7, 1.8.6, 1.8.5, 1.8.4, 1.8.3, 1.8.2, 1.8.1, 1.8.0,
1.7.12, 1.7.11, 1.7.10, 1.7.9, 1.7.8, 1.7.7, 1.7.6, 1.7.5, 1.7.4, 1.7.3, 1.7.2, 1.7.1, 1.7.0,
1.6.5, 1.6.4, 1.6.3, 1.6.2, 1.6.1, 1.6.0,
1.5.6, 1.5.5, 1.5.4, 1.5.3, 1.5.2, 1.5.1, 1.5.0,
1.4.8, 1.4.7, 1.4.6, 1.4.5, 1.4.4, 1.4.3, 1.4.2, 1.4.1, 1.4.0,
1.3.3, 1.3.2, 1.3.1, 1.3.0,
1.2.3, 1.2.2

The project site contains an overview how well these versions were compressed.
Other interesting projects are AngularJS, BackboneJS, Bootstrap, D3, Ember, jQuery, Knockout, lodash, React, Socket.IO, ThreeJS, UnderscoreJS and Vue.

Changelog

Best Zopfli parameters so far:

Size	Improvement	Parameters	Found
38806 bytes	-1 byte	zopfli --i1000000 --mls16384 --bsr25 --lazy --ohh	February 26, 2020 @ 23:47
38807 bytes	-2 bytes	zopfli --i100000 --mls16384 --bsr25 --lazy --ohh	December 2, 2015 @ 14:56
38809 bytes	-2 bytes	zopfli --i100000 --mls16384 --bsr18 --lazy --ohh	December 2, 2015 @ 12:20
38811 bytes	-6 bytes	zopfli --i10000 --mls16384 --bsr18 --lazy --ohh	November 22, 2015 @ 22:21
38817 bytes	-1 byte	zopfli --i1000 --mls16384 --bsr18 --lazy --ohh	September 20, 2015 @ 03:39
38818 bytes	-2 bytes	zopfli --i1000 --mls16384 --bsr7 --lazy --ohh	September 14, 2015 @ 15:58
38820 bytes	-1 byte	zopfli --i1000 --mls128 --bsr13 --lazy --ohh	September 14, 2015 @ 15:52
38821 bytes	–	zopfli --i100 --mls16384 --bsr7 --lazy --ohh	September 11, 2015 @ 15:06

If there are multiple parameter sets yielding the same compressed size, only the first one found is shown.

Most recent activity on July 20, 2020 @ 12:48.

Heatmaps

This Zopfli heatmap visualizes how compression changes when modifying the --bsr and --mls parameter.
Cell's contents is the best filesize achieved (in bytes, hover with mouse over cells to see number of iterations).

Good parameters are green, bad are red. The best and worst are bold as well.
The brightness of the blue background color indicates how many iterations were processed:
10,000, 100,000 or 1,000,000.

bsr \ mls	2	4	8	16	32	64	128	256	512	1024	2048	4096	8192	16384	32768
bsr \ mls	2	4	8	16	32	64	128	256	512	1024	2048	4096	8192	16384	32768
2	38834	38833	38832	38826	38825	38833	38830	38830	38831	38833	38830	38832	38829	38828	38828
4	38824	38817	38820	38809	38816	38825	38833	38824	38836	38822	38824	38827	38851	38828	38818
6	38820	38820	38835	38838	38834	38835	38831	38830	38833	38823	38822	38827	38843	38818	38832
7	38816	38815	38831	38832	38832	38833	38815	38815	38824	38827	38827	38835	38843	38809	38820
8	38813	38814	38817	38814	38815	38834	38831	38815	38833	38823	38825	38828	38833	38841	38816
9	38811	38817	38809	38812	38815	38834	38832	38820	38826	38825	38825	38838	38847	38848	38822
10	38820	38823	38809	38834	38818	38815	38816	38816	38836	38822	38826	38837	38843	38820	38818
11	38817	38814	38832	38832	38835	38834	38832	38823	38826	38823	38824	38837	38844	38819	38817
12	38841	38834	38832	38832	38831	38834	38832	38819	38823	38823	38830	38838	38848	38818	38818
13	38815	38814	38836	38832	38832	38815	38811	38816	38825	38823	38823	38836	38846	38810	38817
14	38839	38831	38834	38833	38835	38834	38832	38816	38827	38824	38826	38839	38845	38817	38816
15	38819	38814	38834	38832	38831	38831	38832	38812	38816	38822	38822	38836	38844	38819	38818
16	38819	38815	38815	38821	38816	38833	38835	38821	38828	38823	38823	38836	38847	38818	38816
17	38815	38815	38832	38832	38831	38835	38835	38817	38824	38823	38824	38837	38844	38821	38817
18	38814	38814	38832	38832	38814	38832	38831	38819	38830	38823	38824	38839	38840	38809	38816
19	38814	38816	38832	38815	38823	38835	38830	38832	38823	38823	38824	38839	38838	38818	38817
20	38814	38832	38833	38835	38814	38833	38832	38817	38824	38823	38824	38827	38844	38827	38817
21	38818	38816	38833	38832	38834	38833	38816	38831	38833	38823	38826	38828	38851	38818	38817
22	38815	38815	38834	38832	38816	38832	38830	38819	38824	38822	38825	38837	38843	38820	38819
23	38815	38814	38816	38832	38814	38833	38831	38815	38825	38822	38825	38834	38844	38816	38816
25	38815	38814	38814	38835	38831	38833	38818	38832	38823	38822	38826	38837	38844	38806	38817
30	38814	38814	38834	38834	38815	38835	38831	38815	38824	38823	38826	38835	38844	38819	38818
40	38818	38832	38831	38832	38835	38835	38833	38816	38824	38833	38824	38827	38841	38810	38817

Due to the Monte Carlo design of my search algorithm, not all parameters have reached the same number of iterations yet:

Iterations	Min. Bytes	Reduction	Coverage
100	38821 bytes	–	100%
1,000	38817 bytes	-4 bytes	100%
10,000	38811 bytes	-6 bytes	100%
100,000	38807 bytes	-4 bytes	3.48%
1,000,000	38806 bytes	-1 byte	0.29%
10,000,000	–	–	–

KZIP has far less options available for tuning/optimization. I only played around with the number of blocks (parameter -n):

Blocks	Min. Bytes	Compared To Best Zopfli	Compared To Best KZIP
(any)	38917 bytes	+111 bytes (+0.29%)	+4 bytes
1	38913 bytes	+107 bytes (+0.28%)	–
2	38913 bytes	+107 bytes (+0.28%)	–
3	38955 bytes	+149 bytes (+0.38%)	+42 bytes
4	38924 bytes	+118 bytes (+0.30%)	+11 bytes
5	38963 bytes	+157 bytes (+0.40%)	+50 bytes
6	38989 bytes	+183 bytes (+0.47%)	+76 bytes
7	38974 bytes	+168 bytes (+0.43%)	+61 bytes
8	38938 bytes	+132 bytes (+0.34%)	+25 bytes

Non-DEFLATE Algorithms

Archivers based on completely different compression algorithms often produce superior results.
Unfortunately, browsers only support gzip compression at the moment.
However, support for Brotli is constantly growing - for example, your browser actually supports it !

Algorithm	Program	Parameters	Size	Compared To Best Zopfli
ZPAQ (Wikipedia)	zpaq	zpaq -method 69	29403 bytes	-9403 bytes (-24.23%)
RAR (proprietary)	RAR	rar a -m5 -md64m -mc63:128t -mt1	34060 bytes	-4746 bytes (-12.23%)
PPMd (Wikipedia)	7zip	7za a -mx=9 -m0=ppmd	35660 bytes	-3146 bytes (-8.11%)
Brotli (Wikipedia)	brotli	brotli -q 11	35772 bytes	-3034 bytes (-7.82%)
LZMA2 (Wikipedia)	xz	xz -9	36768 bytes	-2038 bytes (-5.25%)
Burrows-Wheeler transform (Wikipedia)	bzip2	bzip2 -9	37704 bytes	-1102 bytes (-2.84%)
Zstandard (Wikipedia)	zstd	zstd -19	37853 bytes	-953 bytes (-2.46%)

Detailled Analysis

I wrote a DEFLATE decoder in Javascript. Click the button below to start a client-side analysis of the smallest gzipped files (may take a second):

Load and Parse Data

Notes: pigz is a fast open source multi-threaded implementation of gzip written by one of the original authors of gzip.
However, when using compression level 11, pigz actually switches to the slower Zopfli algorithm and isn't multi-threaded anymore.
KrzyMOD's extensions to Zopfli offer the highest level of configuration and is therefore used for my brute-force search.
Ken Silverman wrote the closed-source KZIP compression program and Jonathon Fowler ported it to Linux.
Defluff was created by Joachim Henke; DeflOpt is a tool by Ben Jos Walbeehm.

website made by Stephan Brumme in 2015 and still improving in 2026.
all timestamps are displayed in central european time. see my changelog.
no flash, not even images or external css files - and everything squeezed into a single html file.
which was handsomely compressed before releasing it into the wild internet - obviously.

please visit my homepage and my blog, too.
email: minime (at) stephan-brumme.com

All trademarks are property of their respective owners. You know, the boring legal stuff.