Choose a version:
34% The original file has 247387 bytes (241.6k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 84320 bytes (82.3k, 34%).

After GZIP compression these minified files vary in size:
Microsoft
  37723 bytes (36.8k)
CDN, direct link
Boot
  34461 bytes (33.7k)
CDN, direct link
jsdelivr
  34461 bytes (33.7k)
CDN, direct link
cdnjs
  29798 bytes (29.1k)
CDN, direct link
Baidu
  29779 bytes (29.1k)
CDN, direct link
unpkg
  29607 bytes (28.9k)
CDN, direct link
cdnhttps
  29587 bytes (28.9k)
CDN, direct link
gzip -6 (default)
  29582 bytes (28.9k)
local copy
gzip -9
  29527 bytes (28.8k)
local copy
Google
  29524 bytes (28.8k)
CDN, direct link
7zip -mx=9 -tgzip
  28582 bytes (27.9k)
local copy
libdeflate -12
  28537 bytes (27.9k)
local copy
Yandex
  28520 bytes (27.9k)
CDN, direct link
pigz -11 -n
  28520 bytes (27.9k)
local copy
kzip -s0 -rn -b2
  28500 bytes (27.8k)
local copy
Zopfli
  28487 bytes (27.8k)
local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/jquery/jquery-2.1.3.min.js

You will automatically get the smallest jQuery 2.1.3 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 33 bytes by using my jQuery 2.1.3 Zopfli version instead of the best available CDN (0.12% smaller than Yandex, 28487 vs. 28520 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 --mls2048 --bsr12 --lazy --ohh

(found September 5, 2015)
Description Value Parameter
iterations 100000  --i100000
maximum blocks 8  --mb8
maximum length score 2048  --mls2048
block splitting recursion 12  --bsr12
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 http://code.jquery.com/jquery-2.1.3.min.js --location | md5sum
32015dd42e9582a80a84736f5d9a44d7  -
curl --silent --compressed http://minime.stephan-brumme.com/files/jquery/jquery-2.1.3.min.zopfli.js.gz | md5sum
32015dd42e9582a80a84736f5d9a44d7  -

SHA1:
curl --silent --compressed http://code.jquery.com/jquery-2.1.3.min.js --location | sha1sum
41b4bfbaa96be6d1440db6e78004ade1c134e276  -
curl --silent --compressed http://minime.stephan-brumme.com/files/jquery/jquery-2.1.3.min.zopfli.js.gz | sha1sum
41b4bfbaa96be6d1440db6e78004ade1c134e276  -

These CDNs send you the original file:
CDN Size (compressed) MD5 (uncompressed) Timestamp
Microsoft 37723 bytes 32015dd42e9582a80a84736f5d9a44d7 December 31, 2014 @ 18:54
Google 29524 bytes 32015dd42e9582a80a84736f5d9a44d7 December 19, 2014 @ 16:56
Yandex 28520 bytes 32015dd42e9582a80a84736f5d9a44d7 June 15, 2015 @ 21:17

And some CDNs send you a different file:
CDN Size (compressed) MD5 (uncompressed) Comment / Diff Timestamp
Boot 34461 bytes 7f9fb969ce353c5d77707836391eb28d > //# sourceMappingURL=jquery.min.map
March 18, 2015 @ 09:44
jsdelivr 34461 bytes 7f9fb969ce353c5d77707836391eb28d > //# sourceMappingURL=jquery.min.map
December 20, 2014 @ 15:45
cdnjs 29798 bytes 7f9fb969ce353c5d77707836391eb28d > //# sourceMappingURL=jquery.min.map
December 18, 2014 @ 18:00
Baidu 29779 bytes 8e65e8606c70994e503ac69ba288f9f2 only whitespaces differ July 3, 2015 @ 09:27
unpkg 29607 bytes 7f9fb969ce353c5d77707836391eb28d > //# sourceMappingURL=jquery.min.map
July 11, 2016 @ 15:39
cdnhttps 29587 bytes 7f9fb969ce353c5d77707836391eb28d only different sourceMappingURL December 24, 2015 @ 07:33

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

Other Versions

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

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
28487 bytes -1 byte zopfli --i100000 --mls2048 --bsr12 --lazy --ohh September 5, 2015 @ 02:30
28488 bytes -1 byte zopfli --i1000000 --mls4096 --bsr8 --lazy --ohh September 2, 2015 @ 07:46
28489 bytes -3 bytes zopfli --i100000 --mls4096 --bsr8 --lazy --ohh September 1, 2015 @ 20:52
28492 bytes -1 byte zopfli --i10000 --mls4096 --bsr8 --lazy --ohh September 1, 2015 @ 20:35
28493 bytes -1 byte zopfli --i1000 --mls4096 --bsr8 --lazy --ohh September 1, 2015 @ 20:31
28494 bytes zopfli --i100 --mls4096 --bsr16 --lazy --ohh September 1, 2015 @ 20:21

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

Most recent activity on July 11, 2016 @ 15:39.

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, 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
28506 28506 28505 28506 28507 28507 28506 28506 28503 28490 28489 28490 28491 28495 28506
28509 28510 28511 28510 28511 28503 28508 28500 28500 28491 28490 28489 28501 28492 28510
28502 28500 28502 28501 28500 28511 28507 28500 28504 28490 28495 28490 28491 28493 28504
28504 28500 28510 28502 28506 28500 28499 28504 28502 28503 28492 28492 28500 28493 28505
28503 28500 28496 28499 28508 28500 28507 28500 28503 28489 28488 28488 28501 28492 28503
28502 28501 28510 28502 28502 28498 28508 28497 28502 28501 28500 28489 28498 28493 28503
28498 28509 28511 28512 28510 28502 28498 28497 28501 28500 28489 28490 28498 28492 28503
28503 28499 28509 28508 28508 28502 28498 28503 28501 28501 28488 28489 28501 28493 28503
28503 28500 28509 28509 28512 28511 28498 28499 28501 28502 28487 28490 28498 28493 28503
28504 28502 28500 28502 28503 28500 28502 28500 28501 28502 28494 28490 28498 28494 28503
28502 28502 28509 28500 28502 28500 28510 28498 28500 28500 28495 28489 28496 28493 28503
28502 28509 28502 28507 28501 28500 28498 28500 28504 28503 28489 28493 28501 28493 28504
28502 28501 28512 28512 28502 28499 28510 28500 28501 28500 28489 28489 28502 28494 28504
28503 28501 28504 28501 28502 28509 28510 28498 28503 28503 28493 28493 28506 28493 28503
28503 28501 28501 28512 28502 28510 28498 28500 28504 28504 28488 28493 28500 28493 28504
28498 28501 28509 28505 28501 28511 28499 28500 28502 28494 28488 28492 28492 28493 28504
28504 28511 28509 28501 28502 28497 28499 28499 28503 28494 28492 28494 28501 28493 28504
28502 28499 28509 28509 28504 28498 28499 28500 28504 28504 28487 28493 28503 28493 28503
28503 28510 28509 28500 28502 28510 28499 28500 28503 28504 28500 28492 28500 28493 28504
28502 28509 28509 28509 28509 28509 28510 28500 28504 28492 28500 28493 28502 28494 28504
28503 28501 28510 28503 28502 28510 28498 28498 28507 28504 28488 28493 28502 28493 28504
28497 28500 28512 28501 28502 28509 28510 28499 28504 28503 28492 28493 28501 28493 28504
28502 28511 28510 28502 28501 28510 28509 28500 28504 28504 28497 28493 28501 28494 28505

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 28492 bytes 100%
1,000 28492 bytes 100%
10,000 28491 bytes -1 byte 100%
100,000 28487 bytes -4 bytes 17.39%
1,000,000 28487 bytes 0.58%
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
28590 bytes +103 bytes (+0.36%) +90 bytes
28589 bytes +102 bytes (+0.36%) +89 bytes
28500 bytes +13 bytes (+0.05%)
28513 bytes +26 bytes (+0.09%) +13 bytes
28523 bytes +36 bytes (+0.13%) +23 bytes
28564 bytes +77 bytes (+0.27%) +64 bytes
28597 bytes +110 bytes (+0.39%) +97 bytes
28635 bytes +148 bytes (+0.52%) +135 bytes
28671 bytes +184 bytes (+0.65%) +171 bytes

Non-DEFLATE Algorithms

Archivers based on completely different compression algorithms often produce superior results.
Unfortunately, browsers only support gzip compression at the moment.
Algorithm Program Parameters Size Compared To Best Zopfli
ZPAQ (Wikipedia) zpaq zpaq -method 69 23664 bytes -4823 bytes (-16.93%)
RAR (proprietary) RAR rar a -m5 -md64m -mc63:128t -mt1 24152 bytes -4335 bytes (-15.22%)
PPMd (Wikipedia) 7zip 7za a -mx=9 -m0=ppmd 25450 bytes -3037 bytes (-10.66%)
Brotli (Wikipedia) brotli brotli -q 11 26676 bytes -1811 bytes (-6.36%)
Burrows-Wheeler transform (Wikipedia) bzip2 bzip2 -9 26931 bytes -1556 bytes (-5.46%)
LZMA2 (Wikipedia) xz xz -9 27712 bytes -775 bytes (-2.72%)
ZSTD (Wikipedia) zstd zstd -19 28212 bytes -275 bytes (-0.97%)

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 2017.
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