Choose a version:
26% The original file has 639284 bytes (624.3k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 167921 bytes (164.0k, 26%).

After GZIP compression these minified files vary in size:
gzip -6 (default)
  56423 bytes (55.1k)
local copy
gzip -9
  56351 bytes (55.0k)
local copy
libdeflate -12
  53674 bytes (52.4k)
local copy
7zip -mx=9 -tgzip
  53646 bytes (52.4k)
local copy
kzip -s0 -rn -b1
  53574 bytes (52.3k)
local copy
pigz -11 -n
  53572 bytes (52.3k)
local copy
zultra
  53568 bytes (52.3k)
local copy
Zopfli
  53483 bytes (52.2k)
local copy
Zopfli (defluff)
  53482 bytes (52.2k)
local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/dojo/dojo-1.14.9.min.js (or via HTTPS)

You will automatically get the smallest Dojo 1.14.9 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 --mls256 --bsr2 --lazy --ohh

(found March 4, 2022)
Description Value Parameter
iterations 1000000  --i1000000
maximum blocks 8  --mb8
maximum length score 256  --mls256
block splitting recursion 2  --bsr2
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 (53482 bytes).

Verify file integrity

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

MD5:
curl --silent --compressed https://download.dojotoolkit.org/release-1.14.9/dojo.js --location | md5sum
3ce962df7124dddf37cef2a53a3f6f2f  -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.14.9.min.zopfli.js.gz | md5sum
3ce962df7124dddf37cef2a53a3f6f2f  -

SHA1:
curl --silent --compressed https://download.dojotoolkit.org/release-1.14.9/dojo.js --location | sha1sum
5aa7b2fee97ec118052f66ba8f50d639b241fde2  -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.14.9.min.zopfli.js.gz | sha1sum
5aa7b2fee97ec118052f66ba8f50d639b241fde2  -

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
53483 bytes -4 bytes zopfli --i1000000 --mls256 --bsr2 --lazy --ohh March 4, 2022 @ 01:25
53487 bytes -1 byte zopfli --i100000 --mls256 --bsr2 --lazy --ohh March 3, 2022 @ 16:16
53488 bytes -4 bytes zopfli --i100000 --mls128 --bsr40 --lazy --ohh March 3, 2022 @ 13:34
53492 bytes -1 byte zopfli --i10000 --mls128 --bsr40 --lazy --ohh February 25, 2022 @ 13:54
53493 bytes -1 byte zopfli --i10000 --mls128 --bsr6 --lazy --ohh February 25, 2022 @ 10:25
53494 bytes -1 byte zopfli --i10000 --mls8192 --bsr9 --lazy --ohh February 25, 2022 @ 10:11
53495 bytes -4 bytes zopfli --i10000 --mls8 --bsr30 --lazy --ohh February 25, 2022 @ 05:31
53499 bytes -1 byte zopfli --i1000 --mls128 --bsr6 --lazy --ohh February 24, 2022 @ 20:50
53500 bytes -1 byte zopfli --i1000 --mls32 --bsr40 --lazy --ohh February 24, 2022 @ 17:09
53501 bytes -2 bytes zopfli --i1000 --mls256 --bsr2 --lazy --ohh February 24, 2022 @ 17:07
53503 bytes zopfli --i100 --mls8192 --bsr9 --lazy --ohh February 24, 2022 @ 15:08

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

Most recent activity on March 4, 2022 @ 10:01.

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
53523 53526 53497 53489 53497 53494 53500 53483 53505 53513 53505 53499 53498 53516 53511
53528 53523 53524 53497 53500 53498 53497 53494 53500 53497 53497 53503 53499 53508 53502
53521 53528 53519 53495 53501 53501 53493 53505 53500 53505 53511 53513 53501 53507 53505
53530 53527 53523 53496 53507 53499 53495 53496 53497 53499 53513 53500 53502 53495 53501
53520 53526 53521 53530 53497 53500 53495 53495 53510 53510 53514 53519 53508 53504 53503
53499 53518 53502 53496 53497 53501 53495 53495 53503 53499 53515 53512 53494 53509 53508
53495 53519 53497 53529 53494 53494 53497 53494 53503 53500 53506 53497 53495 53506 53503
53509 53506 53519 53495 53494 53493 53495 53495 53503 53499 53504 53496 53500 53496 53499
53529 53519 53520 53528 53494 53494 53494 53495 53503 53499 53510 53495 53501 53500 53504
53521 53504 53497 53496 53496 53501 53493 53495 53503 53507 53507 53513 53495 53506 53502
53512 53509 53522 53529 53498 53497 53500 53495 53503 53502 53507 53496 53501 53504 53501
53520 53517 53518 53496 53498 53499 53488 53495 53500 53500 53507 53501 53499 53513 53501
53523 53519 53520 53527 53498 53500 53493 53501 53502 53496 53501 53504 53501 53500 53505
53520 53520 53530 53506 53498 53500 53495 53500 53503 53500 53505 53518 53499 53500 53514
53516 53525 53493 53524 53495 53502 53493 53499 53503 53499 53509 53514 53503 53506 53515
53508 53527 53498 53496 53498 53500 53493 53493 53500 53499 53510 53512 53496 53508 53504
53524 53518 53525 53498 53497 53500 53493 53499 53503 53499 53513 53513 53497 53494 53504
53522 53517 53520 53495 53500 53497 53493 53496 53503 53499 53511 53504 53494 53499 53505
53515 53527 53519 53525 53497 53500 53493 53494 53500 53499 53501 53513 53502 53495 53502
53509 53513 53522 53495 53497 53500 53494 53500 53503 53508 53512 53497 53499 53501 53508
53527 53519 53516 53498 53494 53499 53495 53500 53501 53513 53501 53497 53503 53506 53511
53516 53520 53495 53495 53500 53501 53496 53500 53503 53499 53514 53513 53502 53516 53515
53526 53517 53518 53496 53495 53500 53488 53500 53503 53499 53505 53515 53502 53506 53514

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 53503 bytes 100%
1,000 53499 bytes -4 bytes 100%
10,000 53492 bytes -7 bytes 100%
100,000 53487 bytes -5 bytes 1.16%
1,000,000 53483 bytes -4 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
53663 bytes +180 bytes (+0.34%) +89 bytes
53574 bytes +91 bytes (+0.17%)
53601 bytes +118 bytes (+0.22%) +27 bytes
53636 bytes +153 bytes (+0.29%) +62 bytes
53666 bytes +183 bytes (+0.34%) +92 bytes
53687 bytes +204 bytes (+0.38%) +113 bytes
53730 bytes +247 bytes (+0.46%) +156 bytes
53739 bytes +256 bytes (+0.48%) +165 bytes
53727 bytes +244 bytes (+0.46%) +153 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 39270 bytes -14213 bytes (-26.57%)
RAR (proprietary) RAR rar a -m5 -md64m -mc63:128t -mt1 46932 bytes -6551 bytes (-12.25%)
PPMd (Wikipedia) 7zip 7za a -mx=9 -m0=ppmd 47847 bytes -5636 bytes (-10.54%)
Brotli (Wikipedia) brotli brotli -q 11 49391 bytes -4092 bytes (-7.65%)
LZMA2 (Wikipedia) xz xz -9 50444 bytes -3039 bytes (-5.68%)
Zstandard (Wikipedia) zstd zstd -19 51799 bytes -1684 bytes (-3.15%)
Burrows-Wheeler transform (Wikipedia) bzip2 bzip2 -9 52161 bytes -1322 bytes (-2.47%)

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.