Dojo 1.4.0 - as small as it gets (near-perfect GZIP compression)

Choose a version:

The original file has 375083 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 89264 bytes (87.2k, 24%).

After GZIP compression these minified files vary in size:

Boot	35014 bytes (34.2k)	CDN
Baidu	30529 bytes (29.8k)	CDN
cdnjs	30517 bytes (29.8k)	CDN
gzip -6 (default)	30420 bytes (29.7k)	local copy
gzip -9	30382 bytes (29.7k)	local copy
Sina	30370 bytes (29.7k)	CDN
Yandex	30367 bytes (29.7k)	CDN
libdeflate -12	29062 bytes (28.4k)	local copy
7zip -mx=9 -tgzip	29020 bytes (28.3k)	local copy
kzip -s0 -rn -b0	29001 bytes (28.3k)	local copy
zultra	28968 bytes (28.3k)	local copy
pigz -11 -n	28933 bytes (28.3k)	local copy
Zopfli	28860 bytes (28.2k)	local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/dojo/dojo-1.4.0.min.js (or via HTTPS)

You will automatically get the smallest Dojo 1.4.0 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 1507 bytes by using my Dojo 1.4.0 Zopfli version instead of the best available CDN (5.22% smaller than Yandex, 28860 vs. 30367 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 --mls16 --bsr22 --lazy --ohh

(found February 29, 2020)

Description	Value	Parameter
iterations	1000000	--i1000000
maximum blocks	8	--mb8
maximum length score	16	--mls16
block splitting recursion	22	--bsr22
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-1.4.0/dojo.js --location | md5sum
8f2918241b7c6c7530956d8ed74537a7 -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.4.0.min.zopfli.js.gz | md5sum
8f2918241b7c6c7530956d8ed74537a7 -

SHA1:
curl --silent --compressed https://download.dojotoolkit.org/release-1.4.0/dojo.js --location | sha1sum
c8c84eddc732c3cbf370764836a7712f3f873326 -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.4.0.min.zopfli.js.gz | sha1sum
c8c84eddc732c3cbf370764836a7712f3f873326 -

These CDNs send you the original file:

CDN	Size (compressed)	MD5 (uncompressed)	Timestamp
Boot	35014 bytes	8f2918241b7c6c7530956d8ed74537a7	March 19, 2015 @ 15:30
cdnjs	30517 bytes	8f2918241b7c6c7530956d8ed74537a7	February 8, 2015 @ 14:45
Sina	30370 bytes	8f2918241b7c6c7530956d8ed74537a7	April 25, 2019 @ 14:07
Yandex	30367 bytes	8f2918241b7c6c7530956d8ed74537a7	June 20, 2013 @ 11:59

And some CDNs send you a different file:

CDN	Size (compressed)	MD5 (uncompressed)	Comment / Diff	Timestamp
Baidu	30529 bytes	affef347e2bc428b8e2c3a297b3c1014	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
28860 bytes	-2 bytes	zopfli --i1000000 --mls16 --bsr22 --lazy --ohh	February 29, 2020 @ 14:41
28862 bytes	-2 bytes	zopfli --i100000 --mls16 --bsr22 --lazy --ohh	December 1, 2015 @ 15:08
28864 bytes	-6 bytes	zopfli --i10000 --mls16 --bsr22 --lazy --ohh	November 22, 2015 @ 22:10
28870 bytes	-7 bytes	zopfli --i1000 --mls16 --bsr22 --lazy --ohh	September 22, 2015 @ 05:00
28877 bytes	–	zopfli --i100 --mls16 --bsr22 --lazy --ohh	September 21, 2015 @ 11:54

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 @ 12:51.

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	28931	28940	28945	28945	28939	28964	28952	28951	28958	28955	28955	28907	28964	28953	28952
4	28919	28941	28913	28944	28920	28910	28903	28922	28924	28921	28909	28954	28952	28955	28958
6	28915	28914	28914	28913	28920	28909	28922	28912	28928	28917	28920	28957	28966	28954	28954
7	28917	28933	28931	28916	28916	28916	28925	28916	28944	28947	28944	28956	28953	28953	28949
8	28939	28907	28930	28912	28923	28921	28912	28921	28929	28917	28917	28900	28954	28952	28952
9	28933	28920	28917	28924	28921	28913	28926	28903	28918	28925	28927	28953	28910	28947	28949
10	28920	28936	28921	28924	28906	28905	28923	28938	28913	28950	28911	28953	28909	28954	28950
11	28922	28931	28914	28902	28919	28914	28905	28914	28923	28948	28916	28948	28895	28945	28950
12	28922	28911	28917	28925	28911	28911	28915	28923	28919	28904	28923	28942	28952	28949	28954
13	28918	28907	28913	28901	28902	28911	28904	28919	28922	28945	28914	28881	28948	28946	28946
14	28919	28905	28901	28904	28911	28904	28907	28917	28925	28909	28916	28954	28897	28949	28950
15	28916	28905	28910	28910	28908	28908	28912	28915	28921	28903	28919	28955	28898	28951	28951
16	28908	28908	28899	28909	28918	28906	28909	28920	28908	28915	28898	28948	28961	28954	28951
17	28925	28913	28893	28911	28920	28904	28914	28913	28932	28910	28920	28947	28924	28952	28952
18	28930	28892	28896	28913	28882	28923	28918	28925	28939	28911	28917	28948	28949	28950	28950
19	28928	28920	28927	28908	28905	28921	28914	28905	28944	28923	28950	28949	28935	28951	28951
20	28889	28892	28896	28889	28896	28925	28915	28921	28908	28953	28922	28949	28891	28956	28947
21	28921	28910	28909	28910	28918	28894	28913	28906	28918	28911	28921	28946	28934	28952	28956
22	28891	28892	28926	28860	28907	28921	28917	28922	28911	28926	28912	28955	28900	28955	28953
23	28920	28905	28906	28903	28905	28910	28914	28914	28912	28906	28923	28955	28899	28945	28946
25	28917	28901	28934	28907	28908	28912	28914	28923	28920	28904	28908	28895	28896	28951	28951
30	28916	28927	28914	28905	28905	28914	28915	28930	28920	28906	28916	28948	28893	28954	28946
40	28918	28906	28930	28910	28906	28911	28913	28923	28931	28904	28916	28957	28964	28952	28952

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	28877 bytes	–	100%
1,000	28870 bytes	-7 bytes	100%
10,000	28864 bytes	-6 bytes	100%
100,000	28862 bytes	-2 bytes	1.16%
1,000,000	28860 bytes	-2 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)	29001 bytes	+141 bytes (+0.49%)	–
1	29008 bytes	+148 bytes (+0.51%)	+7 bytes
2	29045 bytes	+185 bytes (+0.64%)	+44 bytes
3	29016 bytes	+156 bytes (+0.54%)	+15 bytes
4	29038 bytes	+178 bytes (+0.62%)	+37 bytes
5	29028 bytes	+168 bytes (+0.58%)	+27 bytes
6	29022 bytes	+162 bytes (+0.56%)	+21 bytes
7	29028 bytes	+168 bytes (+0.58%)	+27 bytes
8	29071 bytes	+211 bytes (+0.73%)	+70 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	22984 bytes	-5876 bytes (-20.36%)
RAR (proprietary)	RAR	rar a -m5 -md64m -mc63:128t -mt1	25764 bytes	-3096 bytes (-10.73%)
PPMd (Wikipedia)	7zip	7za a -mx=9 -m0=ppmd	26620 bytes	-2240 bytes (-7.76%)
Brotli (Wikipedia)	brotli	brotli -q 11	26825 bytes	-2035 bytes (-7.05%)
LZMA2 (Wikipedia)	xz	xz -9	27704 bytes	-1156 bytes (-4.01%)
Zstandard (Wikipedia)	zstd	zstd -19	28459 bytes	-401 bytes (-1.39%)
Burrows-Wheeler transform (Wikipedia)	bzip2	bzip2 -9	28576 bytes	-284 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.