Dojo 1.8.5 - as small as it gets (near-perfect GZIP compression)

Choose a version:

The original file has 602292 bytes (588.2k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 157283 bytes (153.6k, 26%).

After GZIP compression these minified files vary in size:

Boot	62404 bytes (60.9k)	CDN
cdnjs	54108 bytes (52.8k)	CDN
gzip -6 (default)	53871 bytes (52.6k)	local copy
gzip -9	53806 bytes (52.5k)	local copy
7zip -mx=9 -tgzip	51210 bytes (50.0k)	local copy
libdeflate -12	51183 bytes (50.0k)	local copy
kzip -s0 -rn -b1	51134 bytes (49.9k)	local copy
zultra	51130 bytes (49.9k)	local copy
pigz -11 -n	51118 bytes (49.9k)	local copy
Zopfli	51019 bytes (49.8k)	local copy
Zopfli (defluff)	51018 bytes (49.8k)	local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/dojo/dojo-1.8.5.min.js (or via HTTPS)

You will automatically get the smallest Dojo 1.8.5 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 3089 bytes by using my Dojo 1.8.5 Zopfli version instead of the best available CDN (6.05% smaller than cdnjs, 51019 vs. 54108 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 --bsr11 --lazy --ohh

(found February 25, 2020)

Description	Value	Parameter
iterations	1000000	--i1000000
maximum blocks	8	--mb8
maximum length score	16	--mls16
block splitting recursion	11	--bsr11
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 (51018 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-1.8.5/dojo.js --location | md5sum
42baf02400007d06b7a84600a4e3ddd5 -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.8.5.min.zopfli.js.gz | md5sum
42baf02400007d06b7a84600a4e3ddd5 -

SHA1:
curl --silent --compressed https://download.dojotoolkit.org/release-1.8.5/dojo.js --location | sha1sum
2ff64957bb3d629d97f31cd1f292ebd7eb963360 -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.8.5.min.zopfli.js.gz | sha1sum
2ff64957bb3d629d97f31cd1f292ebd7eb963360 -

All listed CDNs deliver identical contents:

CDN	Size (compressed)	MD5 (uncompressed)	Timestamp
Boot	62404 bytes	42baf02400007d06b7a84600a4e3ddd5	March 19, 2015 @ 15:39
cdnjs	54108 bytes	42baf02400007d06b7a84600a4e3ddd5	February 8, 2015 @ 14:45

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
51019 bytes	-1 byte	zopfli --i1000000 --mls16 --bsr11 --lazy --ohh	February 25, 2020 @ 00:06
51020 bytes	-5 bytes	zopfli --i100000 --mls16 --bsr11 --lazy --ohh	December 3, 2015 @ 13:34
51025 bytes	-3 bytes	zopfli --i10000 --mls16384 --bsr25 --lazy --ohh	October 13, 2015 @ 20:00
51028 bytes	-1 byte	zopfli --i1000 --mls16384 --bsr25 --lazy --ohh	September 23, 2015 @ 03:03
51029 bytes	-1 byte	zopfli --i1000 --mls16 --bsr11 --lazy --ohh	September 19, 2015 @ 12:59
51030 bytes	-1 byte	zopfli --i1000 --mls16 --bsr13 --lazy --ohh	September 19, 2015 @ 12:48
51031 bytes	-1 byte	zopfli --i1000 --mls64 --bsr10 --lazy --ohh	September 12, 2015 @ 15:48
51032 bytes	-4 bytes	zopfli --i1000 --mls512 --bsr11 --lazy --ohh	September 10, 2015 @ 20:10
51036 bytes	-1 byte	zopfli --i1000 --mls512 --bsr2 --lazy --ohh	September 10, 2015 @ 20:10
51037 bytes	–	zopfli --i100 --mls1024 --bsr10 --lazy --ohh	September 10, 2015 @ 15:05

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

Most recent activity on March 16, 2022 @ 21:40.

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	51035	51033	51035	51034	51033	51031	51039	51032	51031	51033	51036	51054	51061	51047	51031
4	51037	51034	51032	51029	51036	51034	51036	51043	51035	51039	51041	51044	51053	51042	51036
6	51029	51038	51028	51028	51031	51039	51035	51036	51034	51030	51048	51049	51052	51038	51035
7	51026	51051	51051	51092	51028	51051	51037	51030	51034	51050	51036	51045	51057	51031	51054
8	51028	51029	51031	51025	51027	51046	51033	51037	51035	51042	51051	51055	51056	51047	51035
9	51028	51035	51030	51039	51026	51035	51036	51043	51042	51042	51047	51050	51050	51046	51035
10	51025	51029	51049	51051	51028	51027	51037	51037	51033	51030	51033	51051	51052	51045	51033
11	51029	51030	51055	51019	51028	51030	51038	51033	51029	51037	51046	51052	51036	51040	51034
12	51026	51019	51051	51031	51022	51033	51034	51033	51034	51049	51040	51050	51054	51029	51035
13	51036	51026	51031	51020	51027	51034	51035	51033	51034	51038	51030	51050	51049	51037	51035
14	51026	51056	51052	51093	51027	51027	51039	51034	51041	51047	51029	51049	51050	51037	51035
15	51030	51023	51028	51055	51027	51049	51035	51033	51035	51047	51041	51050	51047	51036	51035
16	51025	51027	51027	51097	51027	51035	51036	51034	51034	51048	51030	51050	51056	51038	51034
17	51030	51029	51031	51055	51027	51090	51034	51033	51041	51037	51046	51051	51052	51032	51035
18	51030	51028	51029	51030	51033	51035	51034	51034	51036	51038	51051	51050	51052	51032	51034
19	51027	51030	51028	51051	51027	51027	51036	51033	51035	51042	51045	51050	51050	51035	51035
20	51026	51021	51027	51029	51027	51035	51034	51029	51048	51040	51046	51050	51054	51034	51035
21	51024	51029	51031	51051	51027	51035	51034	51030	51035	51039	51030	51050	51055	51038	51035
22	51021	51029	51032	51028	51028	51027	51035	51035	51033	51037	51047	51050	51053	51035	51035
23	51029	51028	51031	51022	51029	51089	51035	51029	51034	51048	51044	51046	51056	51033	51033
25	51033	51027	51056	51054	51032	51035	51038	51035	51036	51049	51053	51049	51055	51021	51035
30	51021	51027	51031	51028	51029	51044	51035	51036	51029	51051	51053	51050	51061	51035	51035
40	51024	51029	51028	51028	51027	51035	51034	51028	51031	51048	51049	51046	51052	51034	51035

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	51033 bytes	–	100%
1,000	51028 bytes	-5 bytes	100%
10,000	51025 bytes	-3 bytes	100%
100,000	51020 bytes	-5 bytes	4.35%
1,000,000	51019 bytes	-1 byte	0.87%
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)	51192 bytes	+173 bytes (+0.34%)	+58 bytes
1	51134 bytes	+115 bytes (+0.23%)	–
2	51153 bytes	+134 bytes (+0.26%)	+19 bytes
3	51196 bytes	+177 bytes (+0.35%)	+62 bytes
4	51216 bytes	+197 bytes (+0.39%)	+82 bytes
5	51242 bytes	+223 bytes (+0.44%)	+108 bytes
6	51254 bytes	+235 bytes (+0.46%)	+120 bytes
7	51283 bytes	+264 bytes (+0.52%)	+149 bytes
8	51288 bytes	+269 bytes (+0.53%)	+154 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	37526 bytes	-13493 bytes (-26.45%)
RAR (proprietary)	RAR	rar a -m5 -md64m -mc63:128t -mt1	44393 bytes	-6626 bytes (-12.99%)
PPMd (Wikipedia)	7zip	7za a -mx=9 -m0=ppmd	45702 bytes	-5317 bytes (-10.42%)
Brotli (Wikipedia)	brotli	brotli -q 11	46860 bytes	-4159 bytes (-8.15%)
LZMA2 (Wikipedia)	xz	xz -9	47956 bytes	-3063 bytes (-6.00%)
Burrows-Wheeler transform (Wikipedia)	bzip2	bzip2 -9	49223 bytes	-1796 bytes (-3.52%)
Zstandard (Wikipedia)	zstd	zstd -19	49406 bytes	-1613 bytes (-3.16%)

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.