Dojo 1.6.1 - as small as it gets (near-perfect GZIP compression)

Choose a version:

The original file has 380183 bytes (371.3k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 91801 bytes (89.6k, 24%).

After GZIP compression these minified files vary in size:

Boot	36000 bytes (35.2k)	CDN
Baidu	31478 bytes (30.7k)	CDN
cdnjs	31470 bytes (30.7k)	CDN
gzip -6 (default)	31377 bytes (30.6k)	local copy
gzip -9	31338 bytes (30.6k)	local copy
Yandex	31323 bytes (30.6k)	CDN
7zip -mx=9 -tgzip	29924 bytes (29.2k)	local copy
libdeflate -12	29906 bytes (29.2k)	local copy
kzip -s0 -rn -b3	29898 bytes (29.2k)	local copy
zultra	29885 bytes (29.2k)	local copy
pigz -11 -n	29857 bytes (29.2k)	local copy
Zopfli	29791 bytes (29.1k)	local copy
Zopfli (defluff)	29790 bytes (29.1k)	local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/dojo/dojo-1.6.1.min.js (or via HTTPS)

You will automatically get the smallest Dojo 1.6.1 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 1532 bytes by using my Dojo 1.6.1 Zopfli version instead of the best available CDN (5.14% smaller than Yandex, 29791 vs. 31323 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 --mls8 --bsr30 --lazy --ohh

(found February 27, 2020)

Description	Value	Parameter
iterations	1000000	--i1000000
maximum blocks	8	--mb8
maximum length score	8	--mls8
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 (29790 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-1.6.1/dojo.js --location | md5sum
04279dcba13331b5c49a1cc1445e714f -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.6.1.min.zopfli.js.gz | md5sum
04279dcba13331b5c49a1cc1445e714f -

SHA1:
curl --silent --compressed https://download.dojotoolkit.org/release-1.6.1/dojo.js --location | sha1sum
9dd10b4c5fc7b89073cc04d9f3d22d38f7a6b395 -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.6.1.min.zopfli.js.gz | sha1sum
9dd10b4c5fc7b89073cc04d9f3d22d38f7a6b395 -

These CDNs send you the original file:

CDN	Size (compressed)	MD5 (uncompressed)	Timestamp
Boot	36000 bytes	04279dcba13331b5c49a1cc1445e714f	March 19, 2015 @ 15:32
cdnjs	31470 bytes	04279dcba13331b5c49a1cc1445e714f	February 8, 2015 @ 14:45
Yandex	31323 bytes	04279dcba13331b5c49a1cc1445e714f	June 20, 2013 @ 11:59

And some CDNs send you a different file:

CDN	Size (compressed)	MD5 (uncompressed)	Comment / Diff	Timestamp
Baidu	31478 bytes	ab38681f1e5da0c4b4efa8a53b5e163f	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
29791 bytes	-1 byte	zopfli --i1000000 --mls8 --bsr30 --lazy --ohh	February 27, 2020 @ 18:14
29792 bytes	-3 bytes	zopfli --i100000 --mls8 --bsr30 --lazy --ohh	September 25, 2015 @ 23:45
29795 bytes	-2 bytes	zopfli --i10000 --mls8 --bsr30 --lazy --ohh	September 25, 2015 @ 09:39
29797 bytes	-3 bytes	zopfli --i1000 --mls8 --bsr30 --lazy --ohh	September 24, 2015 @ 21:06
29800 bytes	-1 byte	zopfli --i1000 --mls8 --bsr14 --lazy --ohh	September 20, 2015 @ 05:38
29801 bytes	-3 bytes	zopfli --i1000 --mls8 --bsr16 --lazy --ohh	September 20, 2015 @ 05:29
29804 bytes	–	zopfli --i100 --mls8 --bsr14 --lazy --ohh	September 18, 2015 @ 16:04

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 @ 12:53.

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	29832	29851	29842	29849	29845	29841	29864	29862	29865	29859	29859	29862	29872	29867	29858
4	29835	29836	29831	29836	29840	29844	29850	29854	29849	29854	29846	29852	29855	29862	29853
6	29853	29828	29854	29854	29847	29856	29821	29852	29850	29851	29849	29850	29861	29859	29859
7	29838	29815	29831	29833	29828	29842	29856	29846	29819	29855	29809	29867	29865	29863	29858
8	29819	29831	29808	29832	29839	29835	29827	29827	29834	29855	29852	29859	29867	29859	29859
9	29824	29833	29802	29830	29830	29837	29856	29849	29844	29850	29848	29852	29809	29859	29861
10	29817	29817	29806	29830	29833	29829	29856	29846	29809	29853	29855	29847	29854	29850	29848
11	29824	29830	29826	29833	29831	29836	29848	29846	29826	29850	29841	29856	29809	29850	29846
12	29823	29835	29806	29827	29827	29832	29840	29848	29819	29839	29842	29846	29859	29859	29860
13	29809	29830	29805	29828	29836	29807	29825	29849	29822	29839	29844	29853	29860	29859	29859
14	29799	29819	29794	29818	29817	29821	29807	29847	29810	29837	29842	29853	29806	29860	29861
15	29799	29825	29817	29816	29816	29831	29851	29839	29844	29838	29842	29854	29870	29864	29859
16	29821	29827	29793	29819	29831	29830	29841	29845	29814	29854	29847	29852	29862	29859	29859
17	29822	29826	29821	29833	29828	29839	29852	29847	29820	29852	29848	29859	29810	29860	29859
18	29827	29837	29836	29827	29828	29843	29853	29846	29810	29855	29850	29853	29867	29857	29859
19	29823	29834	29804	29819	29827	29838	29856	29846	29827	29852	29852	29859	29811	29847	29859
20	29834	29834	29806	29829	29827	29844	29855	29849	29812	29853	29813	29846	29868	29847	29853
21	29806	29830	29802	29803	29822	29834	29852	29840	29853	29851	29841	29844	29856	29851	29851
22	29829	29810	29811	29831	29826	29840	29807	29850	29830	29851	29841	29853	29802	29851	29859
23	29803	29837	29801	29824	29825	29834	29829	29846	29816	29851	29841	29856	29859	29849	29850
25	29833	29820	29807	29829	29834	29822	29840	29847	29813	29838	29842	29845	29856	29851	29859
30	29823	29826	29791	29820	29816	29830	29840	29849	29807	29837	29815	29854	29805	29858	29853
40	29805	29829	29801	29833	29826	29843	29841	29846	29820	29839	29805	29856	29860	29852	29859

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	29804 bytes	–	100%
1,000	29797 bytes	-7 bytes	100%
10,000	29795 bytes	-2 bytes	100%
100,000	29792 bytes	-3 bytes	0.87%
1,000,000	29791 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)	29901 bytes	+110 bytes (+0.37%)	+3 bytes
1	29904 bytes	+113 bytes (+0.38%)	+6 bytes
2	29945 bytes	+154 bytes (+0.52%)	+47 bytes
3	29898 bytes	+107 bytes (+0.36%)	–
4	29940 bytes	+149 bytes (+0.50%)	+42 bytes
5	29932 bytes	+141 bytes (+0.47%)	+34 bytes
6	29939 bytes	+148 bytes (+0.50%)	+41 bytes
7	29921 bytes	+130 bytes (+0.44%)	+23 bytes
8	29964 bytes	+173 bytes (+0.58%)	+66 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	23480 bytes	-6311 bytes (-21.18%)
RAR (proprietary)	RAR	rar a -m5 -md64m -mc63:128t -mt1	26437 bytes	-3354 bytes (-11.26%)
PPMd (Wikipedia)	7zip	7za a -mx=9 -m0=ppmd	27442 bytes	-2349 bytes (-7.88%)
Brotli (Wikipedia)	brotli	brotli -q 11	27502 bytes	-2289 bytes (-7.68%)
LZMA2 (Wikipedia)	xz	xz -9	28444 bytes	-1347 bytes (-4.52%)
Zstandard (Wikipedia)	zstd	zstd -19	29249 bytes	-542 bytes (-1.82%)
Burrows-Wheeler transform (Wikipedia)	bzip2	bzip2 -9	29311 bytes	-480 bytes (-1.61%)

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.