Dojo 1.4.1 - as small as it gets (near-perfect GZIP compression)

Choose a version:

The original file has 375088 bytes (366.3k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 89269 bytes (87.2k, 24%).

After GZIP compression these minified files vary in size:

Boot	35016 bytes (34.2k)	CDN
Baidu	30529 bytes (29.8k)	CDN
cdnjs	30520 bytes (29.8k)	CDN
gzip -6 (default)	30422 bytes (29.7k)	local copy
gzip -9	30384 bytes (29.7k)	local copy
Sina	30372 bytes (29.7k)	CDN
libdeflate -12	29065 bytes (28.4k)	local copy
7zip -mx=9 -tgzip	29023 bytes (28.3k)	local copy
kzip -s0 -rn -b1	29012 bytes (28.3k)	local copy
zultra	28972 bytes (28.3k)	local copy
pigz -11 -n	28953 bytes (28.3k)	local copy
Zopfli	28869 bytes (28.2k)	local copy
Zopfli (defluff)	28868 bytes (28.2k)	local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/dojo/dojo-1.4.1.min.js (or via HTTPS)

You will automatically get the smallest Dojo 1.4.1 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 1503 bytes by using my Dojo 1.4.1 Zopfli version instead of the best available CDN (5.21% smaller than Sina, 28869 vs. 30372 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 --i100000 --mb8 --mls64 --bsr30 --lazy --ohh

(found December 1, 2015)

Description	Value	Parameter
iterations	100000	--i100000
maximum blocks	8	--mb8
maximum length score	64	--mls64
block splitting recursion	30	--bsr30
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

Even Smaller Files Thanks To Defluff

Zopfli's output can be further optimized by the defluff tool.
In this particular case, defluff saves 1 more byte (28868 bytes).

Download

Verify file integrity

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

MD5:
curl --silent --compressed https://download.dojotoolkit.org/release-1.4.1/dojo.js --location | md5sum
52547c83649d153a0b2be9149195fbeb -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.4.1.min.zopfli.js.gz | md5sum
52547c83649d153a0b2be9149195fbeb -

SHA1:
curl --silent --compressed https://download.dojotoolkit.org/release-1.4.1/dojo.js --location | sha1sum
73cdd262799aab850abbe694cd3bfb709ea23627 -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.4.1.min.zopfli.js.gz | sha1sum
73cdd262799aab850abbe694cd3bfb709ea23627 -

These CDNs send you the original file:

CDN	Size (compressed)	MD5 (uncompressed)	Timestamp
Boot	35016 bytes	52547c83649d153a0b2be9149195fbeb	March 19, 2015 @ 15:30
cdnjs	30520 bytes	52547c83649d153a0b2be9149195fbeb	February 8, 2015 @ 14:45
Sina	30372 bytes	52547c83649d153a0b2be9149195fbeb	April 25, 2019 @ 14:07

And some CDNs send you a different file:

CDN	Size (compressed)	MD5 (uncompressed)	Comment / Diff	Timestamp
Baidu	30529 bytes	6b66b2b71e2c145b141d52061c6396cb	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
28869 bytes	-4 bytes	zopfli --i100000 --mls64 --bsr30 --lazy --ohh	December 1, 2015 @ 15:06
28873 bytes	-4 bytes	zopfli --i10000 --mls64 --bsr30 --lazy --ohh	September 24, 2015 @ 11:49
28877 bytes	-9 bytes	zopfli --i1000 --mls64 --bsr30 --lazy --ohh	September 24, 2015 @ 11:46
28886 bytes	–	zopfli --i100 --mls64 --bsr30 --lazy --ohh	September 24, 2015 @ 11:09

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	28938	28937	28950	28948	28942	28969	28954	28953	28960	28959	28959	28954	28968	28953	28954
4	28924	28950	28938	28942	28921	28912	28921	28930	28937	28938	28942	28958	28955	28959	28952
6	28916	28922	28916	28920	28926	28913	28922	28945	28934	28957	28934	28960	28969	28958	28954
7	28923	28924	28933	28931	28943	28925	28917	28922	28944	28921	28926	28960	28959	28957	28956
8	28920	28922	28914	28928	28923	28925	28919	28923	28925	28920	28920	28921	28956	28957	28953
9	28933	28924	28920	28918	28929	28915	28917	28909	28942	28955	28929	28952	28938	28956	28949
10	28925	28914	28922	28924	28919	28928	28917	28916	28933	28959	28934	28950	28952	28960	28953
11	28925	28917	28913	28919	28938	28921	28916	28915	28920	28912	28931	28952	28959	28957	28953
12	28919	28915	28918	28926	28917	28910	28918	28920	28926	28920	28928	28950	28956	28950	28953
13	28914	28910	28916	28913	28905	28915	28921	28920	28921	28947	28892	28895	28955	28952	28950
14	28906	28909	28905	28911	28909	28922	28914	28919	28925	28952	28945	28950	28900	28957	28956
15	28902	28914	28937	28917	28909	28909	28915	28923	28920	28905	28942	28959	28957	28958	28962
16	28910	28904	28906	28911	28920	28912	28923	28907	28924	28908	28929	28950	28940	28957	28957
17	28911	28928	28909	28907	28925	28917	28917	28923	28928	28915	28922	28949	28957	28956	28956
18	28918	28894	28896	28923	28909	28914	28920	28912	28927	28911	28939	28950	28896	28957	28960
19	28918	28916	28928	28918	28910	28929	28926	28931	28930	28954	28950	28954	28957	28951	28949
20	28896	28896	28888	28909	28918	28921	28914	28924	28914	28912	28932	28953	28959	28957	28952
21	28917	28921	28925	28917	28909	28893	28919	28906	28931	28914	28917	28952	28937	28951	28955
22	28896	28896	28929	28889	28907	28923	28919	28930	28940	28918	28910	28959	28900	28951	28950
23	28927	28909	28907	28920	28906	28918	28919	28912	28914	28922	28956	28960	28901	28957	28956
25	28906	28910	28931	28909	28920	28911	28918	28917	28924	28907	28911	28896	28895	28950	28955
30	28926	28918	28911	28908	28908	28869	28914	28935	28925	28905	28922	28962	28898	28951	28951
40	28909	28907	28910	28912	28914	28913	28917	28930	28927	28906	28906	28954	28966	28951	28948

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	28886 bytes	–	100%
1,000	28877 bytes	-9 bytes	100%
10,000	28873 bytes	-4 bytes	100%
100,000	28869 bytes	-4 bytes	0.58%
1,000,000	28869 bytes	–	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)	29015 bytes	+146 bytes (+0.51%)	+3 bytes
1	29012 bytes	+143 bytes (+0.50%)	–
2	29049 bytes	+180 bytes (+0.62%)	+37 bytes
3	29020 bytes	+151 bytes (+0.52%)	+8 bytes
4	29041 bytes	+172 bytes (+0.60%)	+29 bytes
5	29031 bytes	+162 bytes (+0.56%)	+19 bytes
6	29023 bytes	+154 bytes (+0.53%)	+11 bytes
7	29035 bytes	+166 bytes (+0.58%)	+23 bytes
8	29073 bytes	+204 bytes (+0.71%)	+61 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	22986 bytes	-5883 bytes (-20.38%)
RAR (proprietary)	RAR	rar a -m5 -md64m -mc63:128t -mt1	25767 bytes	-3102 bytes (-10.75%)
PPMd (Wikipedia)	7zip	7za a -mx=9 -m0=ppmd	26625 bytes	-2244 bytes (-7.77%)
Brotli (Wikipedia)	brotli	brotli -q 11	26840 bytes	-2029 bytes (-7.03%)
LZMA2 (Wikipedia)	xz	xz -9	27712 bytes	-1157 bytes (-4.01%)
Zstandard (Wikipedia)	zstd	zstd -19	28465 bytes	-404 bytes (-1.40%)
Burrows-Wheeler transform (Wikipedia)	bzip2	bzip2 -9	28587 bytes	-282 bytes (-0.98%)

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.