Dojo 1.9.2 - as small as it gets (near-perfect GZIP compression)

Choose a version:

The original file has 616080 bytes (601.6k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 159978 bytes (156.2k, 26%).

After GZIP compression these minified files vary in size:

Boot	63529 bytes (62.0k)	CDN
cdnjs	55058 bytes (53.8k)	CDN
gzip -6 (default)	54820 bytes (53.5k)	local copy
gzip -9	54764 bytes (53.5k)	local copy
jsdelivr	54734 bytes (53.5k)	CDN
7zip -mx=9 -tgzip	52187 bytes (51.0k)	local copy
libdeflate -12	52184 bytes (51.0k)	local copy
pigz -11 -n	52140 bytes (50.9k)	local copy
zultra	52137 bytes (50.9k)	local copy
kzip -s0 -rn -b1	52135 bytes (50.9k)	local copy
Zopfli	51974 bytes (50.8k)	local copy
Zopfli (defluff)	51972 bytes (50.8k)	local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/dojo/dojo-1.9.2.min.js (or via HTTPS)

You will automatically get the smallest Dojo 1.9.2 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 2760 bytes by using my Dojo 1.9.2 Zopfli version instead of the best available CDN (5.31% smaller than jsdelivr, 51974 vs. 54734 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 --bsr9 --lazy --ohh

(found January 30, 2020)

Description	Value	Parameter
iterations	1000000	--i1000000
maximum blocks	8	--mb8
maximum length score	8	--mls8
block splitting recursion	9	--bsr9
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 2 more bytes (51972 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-1.9.2/dojo.js --location | md5sum
2526a26b4cab24307c0b2cecfb2ee5de -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.9.2.min.zopfli.js.gz | md5sum
2526a26b4cab24307c0b2cecfb2ee5de -

SHA1:
curl --silent --compressed https://download.dojotoolkit.org/release-1.9.2/dojo.js --location | sha1sum
3ba36cce7cb070646bbd77d01971edead4bba754 -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.9.2.min.zopfli.js.gz | sha1sum
3ba36cce7cb070646bbd77d01971edead4bba754 -

All listed CDNs deliver identical contents:

CDN	Size (compressed)	MD5 (uncompressed)	Timestamp
Boot	63529 bytes	2526a26b4cab24307c0b2cecfb2ee5de	March 19, 2015 @ 15:42
cdnjs	55058 bytes	2526a26b4cab24307c0b2cecfb2ee5de	February 8, 2015 @ 14:45
jsdelivr	54734 bytes	2526a26b4cab24307c0b2cecfb2ee5de	August 7, 2014 @ 19:16

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
51974 bytes	-3 bytes	zopfli --i1000000 --mls8 --bsr9 --lazy --ohh	January 30, 2020 @ 21:07
51977 bytes	-4 bytes	zopfli --i100000 --mls8 --bsr9 --lazy --ohh	December 3, 2015 @ 17:26
51981 bytes	-4 bytes	zopfli --i10000 --mls8 --bsr9 --lazy --ohh	November 23, 2015 @ 00:05
51985 bytes	-2 bytes	zopfli --i10000 --mls4 --bsr25 --lazy --ohh	October 14, 2015 @ 06:13
51987 bytes	-2 bytes	zopfli --i10000 --mls8 --bsr16 --lazy --ohh	October 13, 2015 @ 20:44
51989 bytes	-6 bytes	zopfli --i1000 --mls8 --bsr9 --lazy --ohh	September 19, 2015 @ 04:25
51995 bytes	–	zopfli --i100 --mls8 --bsr9 --lazy --ohh	September 18, 2015 @ 16:06

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 @ 12:50.

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	52048	52043	52041	52041	52043	52045	52043	52043	52044	52068	52061	52059	52071	52068	52066
4	52040	52046	52051	52044	52044	52039	52056	52045	52048	52051	52050	52058	52047	52056	52041
6	52044	52049	51993	52049	52051	52040	52045	52043	52039	52043	52053	52058	52051	52058	52053
7	52042	52040	52041	52047	52047	52045	52044	52044	52045	52044	52053	52053	52062	52054	52060
8	52041	51996	52055	52039	52038	52040	52041	52039	52039	52062	52060	52047	52049	52043	52055
9	52044	52045	51974	52047	52038	52040	52039	52040	52049	52058	52050	52057	52061	52058	52044
10	52039	52041	52063	52047	52041	52039	52044	52043	52057	52042	52052	52056	52054	52076	52061
11	52039	51999	51988	52041	52039	52039	52041	52039	52042	52044	52047	52060	52052	52050	52052
12	52040	51986	52055	52043	52038	52041	52040	52038	52038	52041	52043	52056	52053	52039	52049
13	52038	52040	51990	52047	52041	52041	52044	52040	52044	52042	52049	52056	52054	52050	52055
14	52000	52004	51986	52048	52039	52041	52050	52040	52040	52038	52049	52057	52057	52043	52054
15	52040	51997	51986	52041	52038	52040	52045	52040	52040	52039	52053	52056	52055	52054	52055
16	52046	51988	51987	52043	52039	52041	52044	52038	52039	52043	52045	52056	52057	52049	52056
17	52042	51979	51987	52040	52038	52041	52044	52039	52043	52043	52048	52056	52049	52044	52053
18	52044	51992	52059	52047	52040	52041	52044	52039	52039	52049	52049	52054	52051	52039	52054
19	52040	51992	51989	52043	52039	52041	52044	52039	52044	52052	52051	52044	52056	52057	52050
20	52039	52000	51987	52043	52044	52040	52039	52041	52042	52038	52056	52056	52065	52065	52050
21	52038	51997	51991	52041	52038	52040	52044	52038	52044	52041	52048	52056	52058	52065	52053
22	52038	51990	52053	52046	52039	52040	52044	52039	52040	52043	52048	52042	52062	52056	52049
23	52039	51998	52054	52047	52040	52041	52044	52039	52040	52040	52049	52056	52054	52058	52053
25	52039	51979	52055	52047	52041	52042	52045	52039	52042	52042	52056	52056	52064	52038	52049
30	52040	51993	52054	52041	52040	52040	52044	52043	52047	52059	52059	52059	52052	52054	52058
40	52039	51980	52054	52047	52039	52040	52045	52040	52044	52043	52060	52043	52066	52044	52054

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	51995 bytes	–	100%
1,000	51989 bytes	-6 bytes	100%
10,000	51981 bytes	-8 bytes	100%
100,000	51977 bytes	-4 bytes	1.16%
1,000,000	51974 bytes	-3 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)	52195 bytes	+221 bytes (+0.43%)	+60 bytes
1	52135 bytes	+161 bytes (+0.31%)	–
2	52150 bytes	+176 bytes (+0.34%)	+15 bytes
3	52193 bytes	+219 bytes (+0.42%)	+58 bytes
4	52216 bytes	+242 bytes (+0.47%)	+81 bytes
5	52236 bytes	+262 bytes (+0.50%)	+101 bytes
6	52274 bytes	+300 bytes (+0.58%)	+139 bytes
7	52280 bytes	+306 bytes (+0.59%)	+145 bytes
8	52293 bytes	+319 bytes (+0.61%)	+158 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	38127 bytes	-13847 bytes (-26.64%)
RAR (proprietary)	RAR	rar a -m5 -md64m -mc63:128t -mt1	45212 bytes	-6762 bytes (-13.01%)
PPMd (Wikipedia)	7zip	7za a -mx=9 -m0=ppmd	46612 bytes	-5362 bytes (-10.32%)
Brotli (Wikipedia)	brotli	brotli -q 11	47626 bytes	-4348 bytes (-8.37%)
LZMA2 (Wikipedia)	xz	xz -9	48832 bytes	-3142 bytes (-6.05%)
Burrows-Wheeler transform (Wikipedia)	bzip2	bzip2 -9	50238 bytes	-1736 bytes (-3.34%)
Zstandard (Wikipedia)	zstd	zstd -19	50270 bytes	-1704 bytes (-3.28%)

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.