jQuery 2.2.1 - as small as it gets (near-perfect GZIP compression)

Choose a version:

The original file has 258549 bytes (252.5k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 85630 bytes (83.6k, 33%).

After GZIP compression these minified files vary in size:

Microsoft	38407 bytes (37.5k)	CDN
Boot	34929 bytes (34.1k)	CDN
cdnjs	30127 bytes (29.4k)	CDN
gzip -6 (default)	29947 bytes (29.2k)	local copy
unpkg	29936 bytes (29.2k)	CDN
gzip -9	29902 bytes (29.2k)	local copy
Google	29895 bytes (29.2k)	CDN
jsdelivr	29892 bytes (29.2k)	CDN
7zip -mx=9 -tgzip	28942 bytes (28.3k)	local copy
libdeflate -12	28890 bytes (28.2k)	local copy
Yandex	28877 bytes (28.2k)	CDN
zultra	28869 bytes (28.2k)	local copy
pigz -11 -n	28868 bytes (28.2k)	local copy
kzip -s0 -rn -b2	28856 bytes (28.2k)	local copy
Zopfli	28829 bytes (28.2k)	local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/jquery/jquery-2.2.1.min.js (or via HTTPS)

You will automatically get the smallest jQuery 2.2.1 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

Save 48 bytes by using my jQuery 2.2.1 Zopfli version instead of the best available CDN (0.17% smaller than Yandex, 28829 vs. 28877 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 --i10000000 --mb8 --mls32 --bsr4 --lazy --ohh

(found February 27, 2016)

Description	Value	Parameter
iterations	10000000	--i10000000
maximum blocks	8	--mb8
maximum length score	32	--mls32
block splitting recursion	4	--bsr4
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

Verify file integrity

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

MD5:
curl --silent --compressed https://code.jquery.com/jquery-2.2.1.min.js --location | md5sum
6cbb321051a268424103cd4aea8ffa66 -
curl --silent --compressed https://minime.stephan-brumme.com/files/jquery/jquery-2.2.1.min.zopfli.js.gz | md5sum
6cbb321051a268424103cd4aea8ffa66 -

SHA1:
curl --silent --compressed https://code.jquery.com/jquery-2.2.1.min.js --location | sha1sum
7cb05e3d551cd61439337b2cb22f49b1955f9711 -
curl --silent --compressed https://minime.stephan-brumme.com/files/jquery/jquery-2.2.1.min.zopfli.js.gz | sha1sum
7cb05e3d551cd61439337b2cb22f49b1955f9711 -

All listed CDNs deliver identical contents:

CDN	Size (compressed)	MD5 (uncompressed)	Timestamp
Microsoft	38407 bytes	6cbb321051a268424103cd4aea8ffa66	February 26, 2016 @ 19:07
Boot	34929 bytes	6cbb321051a268424103cd4aea8ffa66	February 23, 2016 @ 15:02
cdnjs	30127 bytes	6cbb321051a268424103cd4aea8ffa66	February 23, 2016 @ 06:47
unpkg	29936 bytes	6cbb321051a268424103cd4aea8ffa66	July 11, 2016 @ 15:38
Google	29895 bytes	6cbb321051a268424103cd4aea8ffa66	March 18, 2016 @ 22:26
jsdelivr	29892 bytes	6cbb321051a268424103cd4aea8ffa66	February 22, 2016 @ 21:02
Yandex	28877 bytes	6cbb321051a268424103cd4aea8ffa66	(invalid)

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

Other Versions

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

3.6.1, 3.6.0,
3.5.1, 3.5.0,
3.4.1, 3.4.0,
3.3.1, 3.3.0,
3.2.1, 3.2.0,
3.1.1, 3.1.0, 3.0.0,
2.2.4, 2.2.3, 2.2.2, 2.2.1, 2.2.0,
2.1.4, 2.1.3, 2.1.2, 2.1.1, 2.1.0,
2.0.3, 2.0.2, 2.0.1, 2.0.0,
1.12.4, 1.12.3, 1.12.2, 1.12.1, 1.12.0,
1.11.3, 1.11.2, 1.11.1, 1.11.0,
1.10.2, 1.10.1, 1.10.0,
1.9.1, 1.9.0,
1.8.3, 1.8.2, 1.8.1, 1.8.0,
1.7.2, 1.7.1, 1.7.0,
1.6.4, 1.6.3, 1.6.2, 1.6.1, 1.6,
1.5.2, 1.5.1, 1.5,
1.4.4, 1.4.3, 1.4.2, 1.4.1, 1.4,
1.3.2, 1.3.1, 1.3,
1.2.6, 1.2.5, 1.2.4, 1.2.3, 1.2.2, 1.2.1, 1.2,
1.1.4, 1.1.3, 1.1.2, 1.1.1, 1.1,
1.0.4, 1.0.3, 1.0.2, 1.0.1, 1.0

The project site contains an overview how well these versions were compressed.
Other interesting projects are AngularJS, BackboneJS, Bootstrap, D3, Dojo, Ember, Knockout, lodash, React, Socket.IO, ThreeJS, UnderscoreJS and Vue.

Changelog

Best Zopfli parameters so far:

Size	Improvement	Parameters	Found
28829 bytes	-1 byte	zopfli --i10000000 --mls32 --bsr4 --lazy --ohh	February 27, 2016 @ 15:38
28830 bytes	-1 byte	zopfli --i1000000 --mls32 --bsr4 --lazy --ohh	February 24, 2016 @ 16:17
28831 bytes	-1 byte	zopfli --i100000 --mls32 --bsr4 --lazy --ohh	February 24, 2016 @ 11:01
28832 bytes	-1 byte	zopfli --i1000000 --mls64 --bsr20 --lazy --ohh	February 23, 2016 @ 19:54
28833 bytes	-3 bytes	zopfli --i100000 --mls64 --bsr20 --lazy --ohh	February 23, 2016 @ 13:46
28836 bytes	-1 byte	zopfli --i10000 --mls64 --bsr20 --lazy --ohh	February 23, 2016 @ 12:04
28837 bytes	-1 byte	zopfli --i10000 --mls32 --bsr2 --lazy --ohh	February 23, 2016 @ 12:00
28838 bytes	-2 bytes	zopfli --i1000 --mls32 --bsr2 --lazy --ohh	February 23, 2016 @ 11:16
28840 bytes	-1 byte	zopfli --i1000 --mls64 --bsr2 --lazy --ohh	February 23, 2016 @ 11:15
28841 bytes	-1 byte	zopfli --i1000 --mls16 --bsr12 --lazy --ohh	February 23, 2016 @ 11:15
28842 bytes	–	zopfli --i100 --mls16 --bsr12 --lazy --ohh	February 23, 2016 @ 10:49

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

Most recent activity on July 20, 2020 @ 12:43.

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, 1,000,000 or 10,000,000.

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	28843	28844	28849	28844	28834	28837	28852	28851	28846	28847	28849	28849	28845	28844	28869
4	28842	28842	28850	28852	28829	28863	28850	28851	28856	28852	28845	28845	28846	28844	28843
6	28851	28846	28850	28853	28854	28852	28852	28850	28850	28851	28843	28846	28845	28848	28844
7	28851	28849	28850	28839	28840	28852	28849	28851	28850	28852	28840	28843	28844	28846	28854
8	28851	28852	28839	28838	28846	28862	28850	28854	28852	28853	28842	28845	28846	28847	28848
9	28852	28850	28842	28839	28840	28863	28850	28850	28852	28853	28840	28846	28845	28848	28849
10	28852	28853	28839	28839	28851	28863	28851	28850	28852	28851	28841	28846	28849	28844	28844
11	28840	28849	28860	28842	28838	28851	28849	28850	28851	28850	28842	28844	28845	28848	28847
12	28852	28850	28840	28840	28851	28867	28851	28852	28850	28853	28840	28844	28845	28848	28849
13	28851	28852	28845	28841	28850	28863	28850	28851	28850	28853	28842	28846	28845	28848	28848
14	28838	28852	28853	28840	28837	28836	28842	28841	28852	28851	28840	28843	28845	28848	28843
15	28852	28852	28844	28854	28858	28852	28849	28850	28853	28850	28840	28843	28843	28846	28848
16	28840	28849	28839	28840	28851	28864	28850	28850	28850	28851	28839	28843	28846	28847	28847
17	28838	28839	28839	28844	28836	28838	28850	28850	28850	28851	28845	28844	28845	28846	28848
18	28851	28849	28840	28855	28842	28841	28850	28837	28850	28852	28842	28846	28845	28848	28849
19	28851	28849	28845	28839	28848	28864	28850	28850	28851	28851	28840	28845	28845	28844	28843
20	28840	28839	28840	28839	28843	28832	28850	28851	28850	28850	28843	28845	28846	28847	28848
21	28841	28850	28839	28840	28844	28843	28850	28839	28850	28851	28841	28845	28845	28846	28847
22	28852	28849	28852	28840	28852	28839	28850	28839	28852	28850	28843	28843	28845	28847	28843
23	28852	28850	28853	28853	28843	28865	28850	28850	28852	28853	28840	28844	28845	28847	28847
25	28839	28841	28840	28840	28852	28843	28850	28850	28851	28851	28843	28844	28845	28846	28842
30	28840	28852	28839	28843	28844	28865	28849	28850	28851	28850	28840	28844	28845	28848	28846
40	28841	28839	28839	28850	28842	28863	28850	28852	28850	28851	28842	28843	28845	28848	28847

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	28842 bytes	–	100%
1,000	28838 bytes	-4 bytes	100%
10,000	28834 bytes	-4 bytes	100%
100,000	28831 bytes	-3 bytes	0.87%
1,000,000	28830 bytes	-1 byte	0.58%
10,000,000	28829 bytes	-1 byte	0.29%

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)	28956 bytes	+127 bytes (+0.44%)	+100 bytes
1	28956 bytes	+127 bytes (+0.44%)	+100 bytes
2	28856 bytes	+27 bytes (+0.09%)	–
3	28864 bytes	+35 bytes (+0.12%)	+8 bytes
4	28873 bytes	+44 bytes (+0.15%)	+17 bytes
5	28920 bytes	+91 bytes (+0.32%)	+64 bytes
6	28941 bytes	+112 bytes (+0.39%)	+85 bytes
7	28992 bytes	+163 bytes (+0.57%)	+136 bytes
8	29029 bytes	+200 bytes (+0.69%)	+173 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	23960 bytes	-4869 bytes (-16.89%)
RAR (proprietary)	RAR	rar a -m5 -md64m -mc63:128t -mt1	24461 bytes	-4368 bytes (-15.15%)
PPMd (Wikipedia)	7zip	7za a -mx=9 -m0=ppmd	25919 bytes	-2910 bytes (-10.09%)
Brotli (Wikipedia)	brotli	brotli -q 11	26989 bytes	-1840 bytes (-6.38%)
Burrows-Wheeler transform (Wikipedia)	bzip2	bzip2 -9	27308 bytes	-1521 bytes (-5.28%)
LZMA2 (Wikipedia)	xz	xz -9	28096 bytes	-733 bytes (-2.54%)
Zstandard (Wikipedia)	zstd	zstd -19	28619 bytes	-210 bytes (-0.73%)

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.