Dojo 1.10.2 - as small as it gets (near-perfect GZIP compression)

Choose a version:

The original file has 629493 bytes (614.7k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 163811 bytes (160.0k, 26%).

After GZIP compression these minified files vary in size:

Boot	64880 bytes (63.4k)	CDN
cdnjs	56230 bytes (54.9k)	CDN
gzip -6 (default)	55961 bytes (54.6k)	local copy
gzip -9	55905 bytes (54.6k)	local copy
7zip -mx=9 -tgzip	53256 bytes (52.0k)	local copy
libdeflate -12	53238 bytes (52.0k)	local copy
kzip -s0 -rn -b1	53188 bytes (51.9k)	local copy
pigz -11 -n	53186 bytes (51.9k)	local copy
zultra	53175 bytes (51.9k)	local copy
Zopfli	53009 bytes (51.8k)	local copy
Zopfli (defluff)	53008 bytes (51.8k)	local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/dojo/dojo-1.10.2.min.js (or via HTTPS)

You will automatically get the smallest Dojo 1.10.2 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 3221 bytes by using my Dojo 1.10.2 Zopfli version instead of the best available CDN (6.08% smaller than cdnjs, 53009 vs. 56230 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 --mls2 --bsr9 --lazy --ohh

(found January 29, 2020)

Description	Value	Parameter
iterations	1000000	--i1000000
maximum blocks	8	--mb8
maximum length score	2	--mls2
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 (53008 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-1.10.2/dojo.js --location | md5sum
321676aeb263b361d2d6f4d37987bfc4 -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.10.2.min.zopfli.js.gz | md5sum
321676aeb263b361d2d6f4d37987bfc4 -

SHA1:
curl --silent --compressed https://download.dojotoolkit.org/release-1.10.2/dojo.js --location | sha1sum
b790fa901ab73de2e7653e2ead2d620a9dfd3034 -
curl --silent --compressed https://minime.stephan-brumme.com/files/dojo/dojo-1.10.2.min.zopfli.js.gz | sha1sum
b790fa901ab73de2e7653e2ead2d620a9dfd3034 -

All listed CDNs deliver identical contents:

CDN	Size (compressed)	MD5 (uncompressed)	Timestamp
Boot	64880 bytes	321676aeb263b361d2d6f4d37987bfc4	March 19, 2015 @ 15:28
cdnjs	56230 bytes	321676aeb263b361d2d6f4d37987bfc4	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
53009 bytes	-3 bytes	zopfli --i1000000 --mls2 --bsr9 --lazy --ohh	January 29, 2020 @ 21:57
53012 bytes	-1 byte	zopfli --i100000 --mls2 --bsr9 --lazy --ohh	December 7, 2015 @ 12:37
53013 bytes	-1 byte	zopfli --i100000 --mls2 --bsr16 --lazy --ohh	December 7, 2015 @ 11:09
53014 bytes	-1 byte	zopfli --i100000 --mls4 --bsr12 --lazy --ohh	December 7, 2015 @ 10:33
53015 bytes	-1 byte	zopfli --i10000 --mls2 --bsr8 --lazy --ohh	September 25, 2015 @ 06:44
53016 bytes	-2 bytes	zopfli --i10000 --mls2 --bsr30 --lazy --ohh	September 25, 2015 @ 04:35
53018 bytes	-1 byte	zopfli --i10000 --mls4 --bsr21 --lazy --ohh	September 25, 2015 @ 04:30
53019 bytes	-4 bytes	zopfli --i10000 --mls4 --bsr18 --lazy --ohh	September 25, 2015 @ 02:51
53023 bytes	-1 byte	zopfli --i1000 --mls2 --bsr17 --lazy --ohh	September 22, 2015 @ 14:11
53024 bytes	-1 byte	zopfli --i1000 --mls4 --bsr6 --lazy --ohh	September 21, 2015 @ 14:19
53025 bytes	-2 bytes	zopfli --i1000 --mls4 --bsr15 --lazy --ohh	September 21, 2015 @ 14:12
53027 bytes	–	zopfli --i100 --mls4 --bsr15 --lazy --ohh	September 21, 2015 @ 13:27

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

Most recent activity on March 15, 2022 @ 17:38.

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	53058	53067	53086	53086	53085	53089	53092	53098	53098	53092	53116	53091	53093	53126	53099
4	53024	53027	53038	53028	53086	53088	53096	53104	53089	53097	53096	53098	53104	53094	53094
6	53034	53018	53042	53033	53088	53088	53089	53095	53090	53143	53092	53101	53097	53098	53096
7	53117	53116	53125	53088	53098	53089	53088	53088	53091	53111	53092	53089	53090	53106	53092
8	53013	53021	53036	53042	53082	53089	53096	53093	53088	53090	53105	53104	53101	53101	53090
9	53009	53047	53032	53034	53084	53089	53093	53093	53089	53087	53098	53089	53102	53103	53097
10	53044	53046	53048	53086	53084	53089	53091	53088	53089	53095	53095	53091	53088	53103	53099
11	53013	53020	53032	53087	53086	53083	53100	53099	53088	53094	53097	53101	53097	53094	53089
12	53018	53014	53046	53033	53092	53085	53084	53088	53090	53093	53097	53101	53100	53096	53095
13	53029	53020	53030	53032	53085	53094	53089	53095	53088	53099	53104	53089	53100	53096	53091
14	53013	53019	53038	53043	53085	53084	53084	53089	53098	53111	53095	53089	53097	53100	53090
15	53018	53013	53035	53033	53088	53085	53088	53085	53089	53103	53103	53089	53090	53106	53093
16	53013	53019	53029	53034	53086	53089	53087	53100	53088	53098	53096	53090	53096	53096	53097
17	53013	53023	53026	53033	53087	53087	53095	53093	53088	53098	53100	53089	53099	53097	53092
18	53019	53019	53045	53049	53086	53086	53094	53094	53088	53105	53097	53090	53097	53093	53098
19	53030	53020	53028	53041	53086	53086	53087	53088	53088	53102	53137	53103	53099	53095	53093
20	53063	53067	53087	53087	53087	53086	53093	53094	53088	53099	53095	53089	53091	53097	53096
21	53010	53018	53033	53031	53086	53087	53094	53088	53089	53093	53094	53089	53091	53097	53104
22	53023	53021	53033	53031	53085	53087	53094	53091	53088	53094	53097	53090	53098	53115	53088
23	53068	53059	53107	53087	53087	53084	53104	53087	53089	53097	53097	53089	53088	53112	53089
25	53057	53059	53072	53086	53086	53086	53088	53088	53089	53093	53099	53089	53090	53094	53089
30	53010	53059	53089	53086	53084	53087	53086	53089	53089	53097	53094	53089	53090	53098	53090
40	53013	53026	53028	53031	53085	53083	53087	53087	53088	53093	53099	53089	53089	53098	53090

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	53026 bytes	–	100%
1,000	53023 bytes	-3 bytes	100%
10,000	53015 bytes	-8 bytes	100%
100,000	53012 bytes	-3 bytes	3.19%
1,000,000	53009 bytes	-3 bytes	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)	53258 bytes	+249 bytes (+0.47%)	+70 bytes
1	53188 bytes	+179 bytes (+0.34%)	–
2	53207 bytes	+198 bytes (+0.37%)	+19 bytes
3	53258 bytes	+249 bytes (+0.47%)	+70 bytes
4	53289 bytes	+280 bytes (+0.53%)	+101 bytes
5	53325 bytes	+316 bytes (+0.60%)	+137 bytes
6	53327 bytes	+318 bytes (+0.60%)	+139 bytes
7	53355 bytes	+346 bytes (+0.65%)	+167 bytes
8	53398 bytes	+389 bytes (+0.73%)	+210 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	38850 bytes	-14159 bytes (-26.71%)
RAR (proprietary)	RAR	rar a -m5 -md64m -mc63:128t -mt1	46085 bytes	-6924 bytes (-13.06%)
PPMd (Wikipedia)	7zip	7za a -mx=9 -m0=ppmd	47558 bytes	-5451 bytes (-10.28%)
Brotli (Wikipedia)	brotli	brotli -q 11	48655 bytes	-4354 bytes (-8.21%)
LZMA2 (Wikipedia)	xz	xz -9	49772 bytes	-3237 bytes (-6.11%)
Zstandard (Wikipedia)	zstd	zstd -19	51253 bytes	-1756 bytes (-3.31%)
Burrows-Wheeler transform (Wikipedia)	bzip2	bzip2 -9	51284 bytes	-1725 bytes (-3.25%)

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.