Choose a version:
33% The original file has 293650 bytes (286.8k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 97180 bytes (94.9k, 33%).

After GZIP compression these minified files vary in size:
Microsoft
  43375 bytes (42.4k)
CDN
Boot
  39459 bytes (38.5k)
CDN
cdnjs
  34033 bytes (33.2k)
CDN
gzip -6 (default)
  33849 bytes (33.1k)
local copy
jsdelivr
  33828 bytes (33.0k)
CDN
cdnhttps
  33820 bytes (33.0k)
CDN
unpkg
  33820 bytes (33.0k)
CDN
Google
  33794 bytes (33.0k)
CDN
gzip -9
  33794 bytes (33.0k)
local copy
7zip -mx=9 -tgzip
  32677 bytes (31.9k)
local copy
libdeflate -12
  32629 bytes (31.9k)
local copy
Yandex
  32604 bytes (31.8k)
CDN
pigz -11 -n
  32596 bytes (31.8k)
local copy
kzip -s0 -rn -b2
  32588 bytes (31.8k)
local copy
Zopfli
  32575 bytes (31.8k)
local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/jquery/jquery-1.12.3.min.js (or via HTTPS)

You will automatically get the smallest jQuery 1.12.3 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 29 bytes by using my jQuery 1.12.3 Zopfli version instead of the best available CDN (0.09% smaller than Yandex, 32575 vs. 32604 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 --i1000000 --mb8 --mls2 --bsr18 --lazy --ohh

(found April 6, 2016)
Description Value Parameter
iterations 1000000  --i1000000
maximum blocks 8  --mb8
maximum length score 2  --mls2
block splitting recursion 18  --bsr18
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-1.12.3.min.js --location | md5sum
c07f2267a050732b752cc3e7a06850ac  -
curl --silent --compressed https://minime.stephan-brumme.com/files/jquery/jquery-1.12.3.min.zopfli.js.gz | md5sum
c07f2267a050732b752cc3e7a06850ac  -

SHA1:
curl --silent --compressed https://code.jquery.com/jquery-1.12.3.min.js --location | sha1sum
220dad6750fba4898e10b8d9b78ca46f4f774544  -
curl --silent --compressed https://minime.stephan-brumme.com/files/jquery/jquery-1.12.3.min.zopfli.js.gz | sha1sum
220dad6750fba4898e10b8d9b78ca46f4f774544  -

All listed CDNs deliver identical contents:
CDN Size (compressed) MD5 (uncompressed) Timestamp
Microsoft 43375 bytes c07f2267a050732b752cc3e7a06850ac April 12, 2016 @ 19:18
Boot 39459 bytes c07f2267a050732b752cc3e7a06850ac May 4, 2016 @ 09:17
cdnjs 34033 bytes c07f2267a050732b752cc3e7a06850ac April 6, 2016 @ 05:46
jsdelivr 33828 bytes c07f2267a050732b752cc3e7a06850ac April 5, 2016 @ 22:38
cdnhttps 33820 bytes c07f2267a050732b752cc3e7a06850ac November 22, 2016 @ 16:35
unpkg 33820 bytes c07f2267a050732b752cc3e7a06850ac July 11, 2016 @ 15:39
Google 33794 bytes c07f2267a050732b752cc3e7a06850ac May 13, 2016 @ 13:12
Yandex 32604 bytes c07f2267a050732b752cc3e7a06850ac (invalid)

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

Other Versions

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

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
32575 bytes -1 byte zopfli --i1000000 --mls2 --bsr18 --lazy --ohh April 6, 2016 @ 21:32
32576 bytes -3 bytes zopfli --i100000 --mls2 --bsr18 --lazy --ohh April 6, 2016 @ 11:15
32579 bytes -2 bytes zopfli --i10000 --mls2 --bsr18 --lazy --ohh April 6, 2016 @ 10:43
32581 bytes -6 bytes zopfli --i1000 --mls2 --bsr18 --lazy --ohh April 6, 2016 @ 10:40
32587 bytes zopfli --i100 --mls2 --bsr18 --lazy --ohh April 6, 2016 @ 10:36

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

Most recent activity on November 22, 2016 @ 16:35.

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
32590 32590 32589 32589 32590 32588 32587 32591 32591 32591 32590 32592 32596 32596 32595
32585 32583 32584 32582 32583 32582 32584 32586 32586 32582 32585 32582 32598 32584 32585
32589 32587 32584 32589 32588 32582 32591 32588 32592 32591 32585 32582 32583 32583 32581
32590 32588 32587 32593 32588 32583 32587 32583 32588 32589 32583 32584 32585 32582 32581
32590 32581 32590 32589 32590 32588 32588 32590 32591 32591 32578 32582 32583 32584 32580
32581 32582 32583 32581 32588 32589 32590 32588 32590 32589 32582 32584 32581 32585 32583
32580 32582 32582 32580 32589 32588 32588 32587 32587 32587 32582 32585 32582 32583 32581
32585 32581 32586 32581 32590 32581 32587 32587 32589 32590 32580 32580 32581 32584 32580
32588 32588 32587 32588 32588 32588 32587 32587 32587 32584 32580 32584 32581 32584 32583
32575 32581 32582 32580 32588 32588 32583 32588 32587 32587 32584 32584 32581 32583 32580
32591 32581 32581 32587 32588 32588 32587 32587 32588 32591 32578 32584 32582 32583 32581
32581 32581 32580 32579 32582 32583 32588 32583 32587 32586 32582 32584 32582 32583 32581
32581 32581 32581 32584 32588 32584 32588 32587 32587 32587 32580 32584 32582 32582 32581
32581 32582 32582 32583 32591 32588 32588 32587 32588 32590 32587 32584 32581 32585 32582
32575 32578 32581 32587 32588 32588 32582 32587 32588 32589 32582 32585 32578 32584 32582
32581 32581 32580 32587 32588 32581 32582 32587 32588 32587 32585 32584 32582 32583 32583
32591 32578 32582 32588 32588 32582 32582 32589 32590 32584 32582 32584 32584 32584 32580
32590 32588 32582 32580 32587 32582 32589 32588 32588 32585 32577 32585 32581 32584 32581
32581 32581 32583 32587 32588 32584 32587 32581 32588 32587 32581 32583 32583 32583 32580
32582 32579 32581 32581 32588 32581 32587 32589 32587 32589 32580 32584 32582 32584 32586
32591 32588 32581 32588 32588 32583 32588 32582 32589 32586 32582 32584 32582 32584 32582
32590 32588 32581 32587 32589 32583 32587 32588 32587 32587 32580 32584 32582 32585 32582
32581 32581 32581 32580 32581 32583 32587 32587 32587 32587 32587 32584 32584 32584 32580

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 32587 bytes 100%
1,000 32581 bytes -6 bytes 100%
10,000 32579 bytes -2 bytes 100%
100,000 32576 bytes -3 bytes 2.90%
1,000,000 32575 bytes -1 byte 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
32680 bytes +105 bytes (+0.32%) +92 bytes
32680 bytes +105 bytes (+0.32%) +92 bytes
32588 bytes +13 bytes (+0.04%)
32602 bytes +27 bytes (+0.08%) +14 bytes
32607 bytes +32 bytes (+0.10%) +19 bytes
32643 bytes +68 bytes (+0.21%) +55 bytes
32674 bytes +99 bytes (+0.30%) +86 bytes
32713 bytes +138 bytes (+0.42%) +125 bytes
32752 bytes +177 bytes (+0.54%) +164 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 26653 bytes -5922 bytes (-18.18%)
RAR (proprietary) RAR rar a -m5 -md64m -mc63:128t -mt1 27401 bytes -5174 bytes (-15.88%)
PPMd (Wikipedia) 7zip 7za a -mx=9 -m0=ppmd 29102 bytes -3473 bytes (-10.66%)
Brotli (Wikipedia) brotli brotli -q 11 30366 bytes -2209 bytes (-6.78%)
Burrows-Wheeler transform (Wikipedia) bzip2 bzip2 -9 30669 bytes -1906 bytes (-5.85%)
LZMA2 (Wikipedia) xz xz -9 31524 bytes -1051 bytes (-3.23%)
Zstandard (Wikipedia) zstd zstd -19 32116 bytes -459 bytes (-1.41%)

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 2018.
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