Dojo 1.15.1 - as small as it gets (near-perfect GZIP compression)

Choose a version:

The original file has 639053 bytes (624.1k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 167756 bytes (163.8k, 26%).

After GZIP compression these minified files vary in size:

gzip -6 (default)	56356 bytes (55.0k)	local copy
gzip -9	56286 bytes (55.0k)	local copy
libdeflate -12	53615 bytes (52.4k)	local copy
7zip -mx=9 -tgzip	53589 bytes (52.3k)	local copy
zultra	53522 bytes (52.3k)	local copy
pigz -11 -n	53518 bytes (52.3k)	local copy
kzip -s0 -rn -b1	53517 bytes (52.3k)	local copy
Zopfli	53425 bytes (52.2k)	local copy
Zopfli (defluff)	53424 bytes (52.2k)	local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/dojo/dojo-1.15.1.min.js (or via HTTPS)

You will automatically get the smallest Dojo 1.15.1 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

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 --mls128 --bsr14 --lazy --ohh

(found December 2, 2019)

Description	Value	Parameter
iterations	100000	--i100000
maximum blocks	8	--mb8
maximum length score	128	--mls128
block splitting recursion	14	--bsr14
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 (53424 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-1.15.1/dojo.js --location | md5sum
a792fbdae81376c56e81c02be6615f82 -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.15.1.min.zopfli.js.gz | md5sum
a792fbdae81376c56e81c02be6615f82 -

SHA1:
curl --silent --compressed https://download.dojotoolkit.org/release-1.15.1/dojo.js --location | sha1sum
d9793c2d7f3b77a894107395e53942655062fc85 -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.15.1.min.zopfli.js.gz | sha1sum
d9793c2d7f3b77a894107395e53942655062fc85 -

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
53425 bytes	-1 byte	zopfli --i100000 --mls128 --bsr14 --lazy --ohh	December 2, 2019 @ 01:21
53426 bytes	-4 bytes	zopfli --i100000 --mls128 --bsr15 --lazy --ohh	December 1, 2019 @ 23:45
53430 bytes	-1 byte	zopfli --i10000 --mls128 --bsr15 --lazy --ohh	November 30, 2019 @ 03:27
53431 bytes	-2 bytes	zopfli --i10000 --mls128 --bsr13 --lazy --ohh	November 30, 2019 @ 00:57
53433 bytes	-1 byte	zopfli --i10000 --mls16 --bsr9 --lazy --ohh	November 30, 2019 @ 00:51
53434 bytes	-1 byte	zopfli --i10000 --mls128 --bsr9 --lazy --ohh	November 30, 2019 @ 00:06
53435 bytes	-1 byte	zopfli --i10000 --mls32 --bsr11 --lazy --ohh	November 29, 2019 @ 23:45
53436 bytes	-2 bytes	zopfli --i10000 --mls32 --bsr12 --lazy --ohh	November 29, 2019 @ 23:27
53438 bytes	-2 bytes	zopfli --i1000 --mls8192 --bsr9 --lazy --ohh	November 29, 2019 @ 21:09
53440 bytes	-3 bytes	zopfli --i1000 --mls4 --bsr11 --lazy --ohh	November 29, 2019 @ 20:25
53443 bytes	-2 bytes	zopfli --i1000 --mls8 --bsr21 --lazy --ohh	November 29, 2019 @ 20:24
53445 bytes	–	zopfli --i100 --mls128 --bsr30 --lazy --ohh	November 29, 2019 @ 19:39

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

Most recent activity on February 24, 2022 @ 15:42.

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	53470	53432	53434	53433	53434	53434	53434	53431	53455	53447	53437	53436	53439	53470	53456
4	53464	53468	53438	53434	53437	53446	53434	53433	53443	53436	53456	53440	53438	53443	53439
6	53469	53480	53433	53438	53438	53445	53429	53444	53444	53444	53447	53456	53441	53451	53447
7	53465	53469	53437	53466	53432	53440	53440	53441	53441	53438	53449	53440	53441	53446	53440
8	53460	53466	53464	53467	53432	53442	53433	53432	53452	53443	53457	53434	53435	53452	53448
9	53445	53464	53432	53433	53432	53436	53434	53426	53441	53442	53446	53434	53432	53456	53442
10	53478	53433	53436	53468	53435	53433	53443	53432	53446	53442	53444	53440	53434	53451	53443
11	53431	53431	53435	53432	53435	53440	53434	53432	53441	53442	53444	53433	53441	53441	53443
12	53465	53468	53464	53440	53436	53432	53433	53426	53441	53443	53448	53440	53440	53447	53441
13	53465	53465	53432	53450	53443	53440	53431	53433	53441	53442	53444	53440	53438	53451	53448
14	53432	53474	53479	53469	53436	53436	53425	53442	53447	53445	53444	53438	53445	53450	53445
15	53464	53469	53431	53435	53447	53443	53425	53433	53442	53442	53456	53441	53433	53454	53445
16	53463	53467	53461	53474	53433	53448	53431	53444	53440	53444	53445	53448	53443	53442	53440
17	53466	53473	53475	53482	53432	53443	53431	53442	53443	53443	53447	53453	53442	53442	53443
18	53464	53432	53432	53467	53435	53432	53431	53443	53443	53443	53446	53438	53441	53446	53453
19	53466	53433	53432	53435	53439	53441	53431	53433	53443	53443	53447	53454	53433	53455	53441
20	53466	53470	53432	53434	53435	53448	53431	53441	53441	53443	53454	53438	53434	53452	53452
21	53466	53470	53432	53468	53438	53435	53431	53432	53441	53443	53447	53433	53445	53451	53441
22	53462	53473	53435	53433	53433	53447	53431	53432	53443	53443	53445	53433	53441	53448	53442
23	53432	53436	53459	53434	53433	53440	53431	53442	53446	53440	53451	53435	53436	53443	53449
25	53463	53463	53432	53432	53433	53434	53431	53449	53445	53445	53445	53445	53447	53451	53447
30	53463	53468	53432	53433	53436	53443	53431	53433	53441	53442	53447	53453	53440	53452	53440
40	53464	53466	53437	53434	53435	53448	53427	53431	53441	53442	53444	53457	53441	53452	53443

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	53445 bytes	–	100%
1,000	53438 bytes	-7 bytes	100%
10,000	53430 bytes	-8 bytes	100%
100,000	53425 bytes	-5 bytes	1.74%
1,000,000	53425 bytes	–	0.58%
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)	53596 bytes	+171 bytes (+0.32%)	+79 bytes
1	53517 bytes	+92 bytes (+0.17%)	–
2	53541 bytes	+116 bytes (+0.22%)	+24 bytes
3	53574 bytes	+149 bytes (+0.28%)	+57 bytes
4	53596 bytes	+171 bytes (+0.32%)	+79 bytes
5	53610 bytes	+185 bytes (+0.35%)	+93 bytes
6	53599 bytes	+174 bytes (+0.33%)	+82 bytes
7	53637 bytes	+212 bytes (+0.40%)	+120 bytes
8	53668 bytes	+243 bytes (+0.45%)	+151 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	39276 bytes	-14149 bytes (-26.48%)
RAR (proprietary)	RAR	rar a -m5 -md64m -mc63:128t -mt1	46902 bytes	-6523 bytes (-12.21%)
PPMd (Wikipedia)	7zip	7za a -mx=9 -m0=ppmd	47824 bytes	-5601 bytes (-10.48%)
Brotli (Wikipedia)	brotli	brotli -q 11	49335 bytes	-4090 bytes (-7.66%)
LZMA2 (Wikipedia)	xz	xz -9	50424 bytes	-3001 bytes (-5.62%)
Zstandard (Wikipedia)	zstd	zstd -19	51750 bytes	-1675 bytes (-3.14%)
Burrows-Wheeler transform (Wikipedia)	bzip2	bzip2 -9	52078 bytes	-1347 bytes (-2.52%)

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.