Choose a version:
26% 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
cdnhttps
  55164 bytes (53.9k)
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
kzip -s0 -rn -b1
  52135 bytes (50.9k)
local copy
Zopfli
  51977 bytes (50.8k)
local copy
Zopfli (defluff)
  51976 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 2757 bytes by using my Dojo 1.9.2 Zopfli version instead of the best available CDN (5.30% smaller than jsdelivr, 51977 vs. 54734 bytes):
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 --mls8 --bsr9 --lazy --ohh

(found December 3, 2015)
Description Value Parameter
iterations 100000  --i100000
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 1 more byte (51976 bytes).

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  -

These CDNs send you the original file:
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

And some CDNs send you a different file:
CDN Size (compressed) MD5 (uncompressed) Comment / Diff Timestamp
cdnhttps 55164 bytes 89de3f0cf0c95cfc4672bd012caef70e < /*
< Copyright (c) 2004-2011, The Dojo Foundation All Rights R [...]
< Available via Academic Free License >= 2.1 OR the modifie [...]
< see: http://dojotoolkit.org/license for details
< */
<
< /*
< This is an optimized version of Dojo, built for deploymen [...]
< development. To get sources and documentation, please vis [...]
<
[...]
December 24, 2015 @ 07:33

Note: only the MD5 hashes are shown to keep things simple.

Other Versions

Available Dojo versions at minime.stephan-brumme.com:

1.14.2, 1.14.1, 1.14.0,
1.13.3, 1.13.2, 1.13.1, 1.13.0,
1.12.4, 1.12.3, 1.12.2, 1.12.1,
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,
1.6.3, 1.6.2, 1.6.1, 1.6.0,
1.5.4, 1.5.3, 1.5.2, 1.5.1, 1.5.0,
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

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
51977 bytes -4 bytes zopfli --i100000 --mls8 --bsr9 --lazy --ohh December 3, 2015 @ 17:27
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 June 16, 2016 @ 14:39.

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 or 100,000.
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
52048 52043 52041 52041 52043 52045 52043 52043 52044 52068 52061 52059 52071 52068 52066
52040 52046 52051 52044 52044 52039 52056 52045 52048 52051 52050 52058 52047 52056 52041
52044 52049 51993 52049 52051 52040 52045 52043 52039 52043 52053 52058 52051 52058 52053
52042 52040 52041 52047 52047 52045 52044 52044 52045 52044 52053 52053 52062 52054 52060
52041 51996 52055 52039 52038 52040 52041 52039 52039 52062 52060 52047 52049 52043 52055
52044 52045 51977 52047 52038 52040 52039 52040 52049 52058 52050 52057 52061 52058 52044
52039 52041 52063 52047 52041 52039 52044 52043 52057 52042 52052 52056 52054 52076 52061
52039 51999 51988 52041 52039 52039 52041 52039 52042 52044 52047 52060 52052 52050 52052
52040 51986 52055 52043 52038 52041 52040 52038 52038 52041 52043 52056 52053 52039 52049
52038 52040 51990 52047 52041 52041 52044 52040 52044 52042 52049 52056 52054 52050 52055
52000 52004 51986 52048 52039 52041 52050 52040 52040 52038 52049 52057 52057 52043 52054
52040 51997 51986 52041 52038 52040 52045 52040 52040 52039 52053 52056 52055 52054 52055
52046 51988 51987 52043 52039 52041 52044 52038 52039 52043 52045 52056 52057 52049 52056
52042 51979 51987 52040 52038 52041 52044 52039 52043 52043 52048 52056 52049 52044 52053
52044 51992 52059 52047 52040 52041 52044 52039 52039 52049 52049 52054 52051 52039 52054
52040 51992 51989 52043 52039 52041 52044 52039 52044 52052 52051 52044 52056 52057 52050
52039 52000 51987 52043 52044 52040 52039 52041 52042 52038 52056 52056 52065 52065 52050
52038 51997 51991 52041 52038 52040 52044 52038 52044 52041 52048 52056 52058 52065 52053
52038 51990 52053 52046 52039 52040 52044 52039 52040 52043 52048 52042 52062 52056 52049
52039 51998 52054 52047 52040 52041 52044 52039 52040 52040 52049 52056 52054 52058 52053
52039 51979 52055 52047 52041 52042 52045 52039 52042 52042 52056 52056 52064 52038 52049
52040 51993 52054 52041 52040 52040 52044 52043 52047 52059 52059 52059 52052 52054 52058
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
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
52195 bytes +218 bytes (+0.42%) +60 bytes
52135 bytes +158 bytes (+0.30%)
52150 bytes +173 bytes (+0.33%) +15 bytes
52193 bytes +216 bytes (+0.42%) +58 bytes
52216 bytes +239 bytes (+0.46%) +81 bytes
52236 bytes +259 bytes (+0.50%) +101 bytes
52274 bytes +297 bytes (+0.57%) +139 bytes
52280 bytes +303 bytes (+0.58%) +145 bytes
52293 bytes +316 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 - but your browser doesn't support it.
Algorithm Program Parameters Size Compared To Best Zopfli
ZPAQ (Wikipedia) zpaq zpaq -method 69 38127 bytes -13850 bytes (-26.65%)
RAR (proprietary) RAR rar a -m5 -md64m -mc63:128t -mt1 45212 bytes -6765 bytes (-13.02%)
PPMd (Wikipedia) 7zip 7za a -mx=9 -m0=ppmd 46612 bytes -5365 bytes (-10.32%)
Brotli (Wikipedia) brotli brotli -q 11 47626 bytes -4351 bytes (-8.37%)
LZMA2 (Wikipedia) xz xz -9 48832 bytes -3145 bytes (-6.05%)
Burrows-Wheeler transform (Wikipedia) bzip2 bzip2 -9 50238 bytes -1739 bytes (-3.35%)
Zstandard (Wikipedia) zstd zstd -19 50270 bytes -1707 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):


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 2018.
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