Dojo 1.5.0 - as small as it gets (near-perfect GZIP compression)

Choose a version:

The original file has 377390 bytes (368.5k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 90277 bytes (88.2k, 24%).

After GZIP compression these minified files vary in size:

Boot	35397 bytes (34.6k)	CDN
Baidu	30915 bytes (30.2k)	CDN
cdnjs	30907 bytes (30.2k)	CDN
gzip -6 (default)	30820 bytes (30.1k)	local copy
gzip -9	30793 bytes (30.1k)	local copy
Yandex	30773 bytes (30.1k)	CDN
Sina	30770 bytes (30.0k)	CDN
libdeflate -12	29422 bytes (28.7k)	local copy
7zip -mx=9 -tgzip	29404 bytes (28.7k)	local copy
kzip -s0 -rn -b1	29386 bytes (28.7k)	local copy
pigz -11 -n	29355 bytes (28.7k)	local copy
zultra	29354 bytes (28.7k)	local copy
Zopfli	29264 bytes (28.6k)	local copy
Zopfli (defluff)	29263 bytes (28.6k)	local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/dojo/dojo-1.5.0.min.js (or via HTTPS)

You will automatically get the smallest Dojo 1.5.0 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 1506 bytes by using my Dojo 1.5.0 Zopfli version instead of the best available CDN (5.15% smaller than Sina, 29264 vs. 30770 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 --bsr22 --lazy --ohh

(found February 28, 2020)

Description	Value	Parameter
iterations	1000000	--i1000000
maximum blocks	8	--mb8
maximum length score	8	--mls8
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

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 (29263 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-1.5.0/dojo.js --location | md5sum
b212742b08f37af01790b45b6190b16e -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.5.0.min.zopfli.js.gz | md5sum
b212742b08f37af01790b45b6190b16e -

SHA1:
curl --silent --compressed https://download.dojotoolkit.org/release-1.5.0/dojo.js --location | sha1sum
5a049c7e19a26a6aa96a2bdcb19ea36ec868f56d -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.5.0.min.zopfli.js.gz | sha1sum
5a049c7e19a26a6aa96a2bdcb19ea36ec868f56d -

These CDNs send you the original file:

CDN	Size (compressed)	MD5 (uncompressed)	Timestamp
Boot	35397 bytes	b212742b08f37af01790b45b6190b16e	March 19, 2015 @ 15:31
cdnjs	30907 bytes	b212742b08f37af01790b45b6190b16e	February 8, 2015 @ 14:45
Yandex	30773 bytes	b212742b08f37af01790b45b6190b16e	June 20, 2013 @ 11:59
Sina	30770 bytes	b212742b08f37af01790b45b6190b16e	April 25, 2019 @ 14:07

And some CDNs send you a different file:

CDN	Size (compressed)	MD5 (uncompressed)	Comment / Diff	Timestamp
Baidu	30915 bytes	d3e7e526e89b2deebf19fc8f362385a0	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
29264 bytes	-1 byte	zopfli --i1000000 --mls8 --bsr22 --lazy --ohh	February 28, 2020 @ 19:49
29265 bytes	-2 bytes	zopfli --i100000 --mls8 --bsr22 --lazy --ohh	December 2, 2015 @ 08:57
29267 bytes	-6 bytes	zopfli --i10000 --mls8 --bsr22 --lazy --ohh	November 22, 2015 @ 22:14
29273 bytes	-4 bytes	zopfli --i1000 --mls8 --bsr22 --lazy --ohh	September 22, 2015 @ 03:19
29277 bytes	–	zopfli --i100 --mls8 --bsr22 --lazy --ohh	September 21, 2015 @ 11:16

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	29301	29305	29309	29311	29329	29342	29340	29339	29343	29348	29349	29357	29341	29348	29338
4	29321	29328	29318	29286	29315	29318	29338	29336	29321	29334	29331	29331	29331	29344	29339
6	29301	29302	29305	29317	29302	29314	29331	29338	29315	29346	29338	29335	29340	29335	29336
7	29328	29318	29309	29313	29299	29283	29336	29305	29327	29345	29339	29331	29327	29338	29339
8	29316	29291	29311	29312	29310	29315	29308	29338	29308	29313	29309	29332	29340	29339	29335
9	29324	29316	29316	29324	29310	29285	29316	29322	29307	29346	29339	29331	29334	29338	29338
10	29299	29294	29316	29304	29308	29322	29316	29329	29291	29342	29282	29337	29332	29332	29332
11	29316	29308	29317	29307	29318	29315	29316	29336	29331	29330	29330	29330	29293	29333	29331
12	29322	29283	29323	29301	29311	29308	29339	29323	29323	29330	29332	29331	29301	29330	29330
13	29308	29309	29317	29294	29305	29289	29324	29320	29305	29330	29328	29332	29293	29337	29338
14	29308	29307	29330	29316	29306	29315	29335	29335	29330	29333	29330	29328	29333	29340	29339
15	29305	29310	29323	29306	29306	29309	29305	29310	29330	29330	29331	29329	29330	29340	29339
16	29292	29307	29315	29298	29314	29306	29310	29337	29292	29331	29336	29332	29333	29339	29337
17	29301	29316	29326	29306	29307	29310	29310	29315	29311	29334	29335	29331	29304	29338	29334
18	29301	29307	29309	29294	29305	29301	29336	29337	29307	29331	29338	29331	29333	29340	29339
19	29307	29315	29305	29308	29301	29286	29334	29310	29309	29345	29337	29330	29304	29340	29335
20	29308	29317	29289	29277	29291	29320	29301	29319	29330	29343	29300	29330	29309	29338	29339
21	29318	29316	29312	29311	29309	29315	29308	29338	29310	29342	29329	29331	29334	29334	29335
22	29293	29315	29264	29275	29286	29314	29334	29338	29327	29330	29337	29328	29333	29336	29334
23	29317	29309	29326	29302	29304	29316	29308	29338	29310	29332	29335	29330	29331	29330	29330
25	29316	29315	29319	29285	29304	29314	29335	29336	29319	29327	29305	29329	29294	29337	29334
30	29303	29306	29320	29320	29300	29312	29331	29338	29302	29331	29330	29331	29333	29336	29334
40	29308	29309	29319	29308	29310	29310	29335	29336	29306	29335	29285	29331	29337	29340	29339

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	29277 bytes	–	100%
1,000	29273 bytes	-4 bytes	100%
10,000	29267 bytes	-6 bytes	100%
100,000	29265 bytes	-2 bytes	1.45%
1,000,000	29264 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)	29391 bytes	+127 bytes (+0.43%)	+5 bytes
1	29386 bytes	+122 bytes (+0.42%)	–
2	29426 bytes	+162 bytes (+0.55%)	+40 bytes
3	29389 bytes	+125 bytes (+0.43%)	+3 bytes
4	29428 bytes	+164 bytes (+0.56%)	+42 bytes
5	29418 bytes	+154 bytes (+0.53%)	+32 bytes
6	29429 bytes	+165 bytes (+0.56%)	+43 bytes
7	29400 bytes	+136 bytes (+0.46%)	+14 bytes
8	29438 bytes	+174 bytes (+0.59%)	+52 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	23188 bytes	-6076 bytes (-20.76%)
RAR (proprietary)	RAR	rar a -m5 -md64m -mc63:128t -mt1	26124 bytes	-3140 bytes (-10.73%)
PPMd (Wikipedia)	7zip	7za a -mx=9 -m0=ppmd	26998 bytes	-2266 bytes (-7.74%)
Brotli (Wikipedia)	brotli	brotli -q 11	27146 bytes	-2118 bytes (-7.24%)
LZMA2 (Wikipedia)	xz	xz -9	28064 bytes	-1200 bytes (-4.10%)
Zstandard (Wikipedia)	zstd	zstd -19	28851 bytes	-413 bytes (-1.41%)
Burrows-Wheeler transform (Wikipedia)	bzip2	bzip2 -9	28932 bytes	-332 bytes (-1.13%)

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.