Choose a version:
26% The original file has 642546 bytes (627.5k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 168845 bytes (164.9k, 26%).

After GZIP compression these minified files vary in size:
gzip -6 (default)
  56588 bytes (55.3k)
local copy
gzip -9
  56520 bytes (55.2k)
local copy
libdeflate -12
  53839 bytes (52.6k)
local copy
7zip -mx=9 -tgzip
  53827 bytes (52.6k)
local copy
kzip -s0 -rn -b1
  53754 bytes (52.5k)
local copy
zultra
  53751 bytes (52.5k)
local copy
pigz -11 -n
  53734 bytes (52.5k)
local copy
Zopfli
  53658 bytes (52.4k)
local copy
Zopfli (defluff)
  53656 bytes (52.4k)
local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/dojo/dojo-1.17.1.min.js (or via HTTPS)

You will automatically get the smallest Dojo 1.17.1 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 --i1000000 --mb8 --mls128 --bsr6 --lazy --ohh

(found March 21, 2022)
Description Value Parameter
iterations 1000000  --i1000000
maximum blocks 8  --mb8
maximum length score 128  --mls128
block splitting recursion 6  --bsr6
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 (53656 bytes).

Verify file integrity

After decompression, my uncompressed files are identical to the original ones:

MD5:
curl --silent --compressed https://download.dojotoolkit.org/release-1.17.1/dojo.js --location | md5sum
f42a4d727eda6fe51fcc2ee33c7564c8  -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.17.1.min.zopfli.js.gz | md5sum
f42a4d727eda6fe51fcc2ee33c7564c8  -

SHA1:
curl --silent --compressed https://download.dojotoolkit.org/release-1.17.1/dojo.js --location | sha1sum
e6c01ec3c87a76d89d9722e07cd9834965efc928  -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.17.1.min.zopfli.js.gz | sha1sum
e6c01ec3c87a76d89d9722e07cd9834965efc928  -

Other Versions

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

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
53658 bytes -2 bytes zopfli --i1000000 --mls128 --bsr6 --lazy --ohh March 21, 2022 @ 23:36
53660 bytes -5 bytes zopfli --i100000 --mls128 --bsr6 --lazy --ohh March 21, 2022 @ 11:42
53665 bytes -8 bytes zopfli --i10000 --mls128 --bsr6 --lazy --ohh March 21, 2022 @ 10:52
53673 bytes -1 byte zopfli --i1000 --mls128 --bsr6 --lazy --ohh March 21, 2022 @ 10:46
53674 bytes -2 bytes zopfli --i1000 --mls256 --bsr8 --lazy --ohh March 21, 2022 @ 10:46
53676 bytes zopfli --i100 --mls128 --bsr6 --lazy --ohh March 21, 2022 @ 10:35

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

Most recent activity on March 22, 2022 @ 08:45.

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
53701 53704 53669 53670 53668 53671 53670 53670 53666 53666 53671 53668 53673 53697 53688
53700 53704 53674 53683 53700 53681 53665 53664 53677 53665 53670 53673 53680 53679 53676
53698 53669 53700 53667 53675 53667 53658 53676 53680 53676 53688 53677 53682 53679 53678
53701 53680 53703 53700 53668 53679 53673 53674 53680 53677 53689 53668 53679 53683 53679
53696 53693 53686 53684 53669 53679 53662 53669 53687 53676 53685 53684 53679 53680 53685
53695 53672 53702 53666 53670 53668 53665 53663 53680 53676 53682 53685 53680 53686 53679
53681 53694 53678 53697 53664 53681 53666 53669 53679 53676 53687 53674 53678 53690 53685
53682 53681 53683 53699 53670 53661 53663 53666 53676 53676 53680 53671 53678 53681 53679
53697 53697 53700 53673 53663 53663 53663 53669 53676 53677 53677 53677 53678 53678 53684
53692 53698 53681 53680 53667 53670 53663 53665 53678 53676 53678 53671 53678 53681 53679
53682 53684 53705 53707 53665 53668 53667 53665 53678 53678 53678 53673 53678 53681 53676
53682 53682 53680 53697 53673 53677 53668 53677 53681 53677 53681 53676 53677 53681 53682
53697 53696 53697 53666 53673 53681 53663 53677 53677 53676 53678 53673 53678 53677 53681
53699 53696 53697 53669 53673 53677 53679 53677 53677 53676 53691 53691 53678 53680 53683
53681 53681 53682 53694 53670 53668 53663 53670 53677 53676 53686 53687 53681 53682 53685
53683 53688 53682 53670 53668 53682 53663 53669 53677 53677 53687 53678 53678 53681 53678
53683 53685 53682 53670 53668 53667 53685 53676 53678 53677 53686 53678 53678 53686 53685
53694 53698 53696 53700 53664 53663 53667 53668 53676 53677 53687 53685 53678 53679 53680
53681 53680 53703 53673 53667 53678 53663 53676 53679 53676 53690 53677 53678 53680 53681
53683 53692 53681 53668 53669 53679 53661 53664 53680 53676 53683 53691 53678 53680 53680
53694 53694 53691 53702 53670 53679 53681 53666 53679 53678 53687 53679 53679 53680 53677
53696 53703 53687 53704 53668 53678 53663 53676 53678 53676 53683 53664 53676 53679 53678
53698 53702 53694 53701 53667 53678 53662 53669 53680 53676 53689 53687 53677 53683 53683

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 53676 bytes 100%
1,000 53673 bytes -3 bytes 100%
10,000 53662 bytes -11 bytes 100%
100,000 53660 bytes -2 bytes 1.74%
1,000,000 53658 bytes -2 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
53827 bytes +169 bytes (+0.31%) +73 bytes
53754 bytes +96 bytes (+0.18%)
53761 bytes +103 bytes (+0.19%) +7 bytes
53793 bytes +135 bytes (+0.25%) +39 bytes
53815 bytes +157 bytes (+0.29%) +61 bytes
53845 bytes +187 bytes (+0.35%) +91 bytes
53889 bytes +231 bytes (+0.43%) +135 bytes
53909 bytes +251 bytes (+0.47%) +155 bytes
53893 bytes +235 bytes (+0.44%) +139 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 39440 bytes -14218 bytes (-26.50%)
RAR (proprietary) RAR rar a -m5 -md64m -mc63:128t -mt1 47084 bytes -6574 bytes (-12.25%)
PPMd (Wikipedia) 7zip 7za a -mx=9 -m0=ppmd 48028 bytes -5630 bytes (-10.49%)
Brotli (Wikipedia) brotli brotli -q 11 49583 bytes -4075 bytes (-7.59%)
LZMA2 (Wikipedia) xz xz -9 50624 bytes -3034 bytes (-5.65%)
Zstandard (Wikipedia) zstd zstd -19 51962 bytes -1696 bytes (-3.16%)
Burrows-Wheeler transform (Wikipedia) bzip2 bzip2 -9 52294 bytes -1364 bytes (-2.54%)

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 2022.
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.