Choose a version:
34% The original file has 284394 bytes (277.7k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 95957 bytes (93.7k, 34%).

After GZIP compression these minified files vary in size:
Microsoft
  42874 bytes (41.9k)
CDN
Boot
  38912 bytes (38.0k)
CDN
cdnjs
  33572 bytes (32.8k)
CDN
Baidu
  33559 bytes (32.8k)
CDN
unpkg
  33368 bytes (32.6k)
CDN
fastcdn
  33343 bytes (32.6k)
CDN
cdnhttps
  33342 bytes (32.6k)
CDN
gzip -6 (default)
  33339 bytes (32.6k)
local copy
Yandex
  33332 bytes (32.6k)
CDN
Google
  33303 bytes (32.5k)
CDN
jsdelivr
  33300 bytes (32.5k)
CDN
gzip -9
  33282 bytes (32.5k)
local copy
libdeflate -12
  32269 bytes (31.5k)
local copy
7zip -mx=9 -tgzip
  32240 bytes (31.5k)
local copy
pigz -11 -n
  32165 bytes (31.4k)
local copy
kzip -s0 -rn -b3
  32157 bytes (31.4k)
local copy
Zopfli
  32138 bytes (31.4k)
local copy
Zopfli (defluff)
  32137 bytes (31.4k)
local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/jquery/jquery-1.11.3.min.js (or via HTTPS)

You will automatically get the smallest jQuery 1.11.3 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 1162 bytes by using my jQuery 1.11.3 Zopfli version instead of the best available CDN (3.62% smaller than jsdelivr, 32138 vs. 33300 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 --mls2048 --bsr11 --lazy --ohh

(found October 21, 2015)
Description Value Parameter
iterations 1000000  --i1000000
maximum blocks 8  --mb8
maximum length score 2048  --mls2048
block splitting recursion 11  --bsr11
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 (32137 bytes).

Verify file integrity

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

MD5:
curl --silent --compressed https://code.jquery.com/jquery-1.11.3.min.js --location | md5sum
895323ed2f7258af4fae2c738c8aea49  -
curl --silent --compressed https://minime.stephan-brumme.com/files/jquery/jquery-1.11.3.min.zopfli.js.gz | md5sum
895323ed2f7258af4fae2c738c8aea49  -

SHA1:
curl --silent --compressed https://code.jquery.com/jquery-1.11.3.min.js --location | sha1sum
276c87ff3e1e3155679c318938e74e5c1b76d809  -
curl --silent --compressed https://minime.stephan-brumme.com/files/jquery/jquery-1.11.3.min.zopfli.js.gz | sha1sum
276c87ff3e1e3155679c318938e74e5c1b76d809  -

These CDNs send you the original file:
CDN Size (compressed) MD5 (uncompressed) Timestamp
fastcdn 33343 bytes 895323ed2f7258af4fae2c738c8aea49 November 4, 2015 @ 10:10
Yandex 33332 bytes 895323ed2f7258af4fae2c738c8aea49 June 15, 2015 @ 21:17

And some CDNs send you a different file:
CDN Size (compressed) MD5 (uncompressed) Comment / Diff Timestamp
Microsoft 42874 bytes f03e5a3bf534f4a738bc350631fd05bd > //# sourceMappingURL=jquery.min.map
April 28, 2015 @ 22:10
Boot 38912 bytes f03e5a3bf534f4a738bc350631fd05bd > //# sourceMappingURL=jquery.min.map
May 3, 2015 @ 00:34
cdnjs 33572 bytes f03e5a3bf534f4a738bc350631fd05bd > //# sourceMappingURL=jquery.min.map
May 1, 2015 @ 20:30
Baidu 33559 bytes 13c0a5055cca7b2463b2f73701960b9e only whitespaces differ June 3, 2015 @ 07:58
unpkg 33368 bytes f03e5a3bf534f4a738bc350631fd05bd > //# sourceMappingURL=jquery.min.map
July 11, 2016 @ 15:39
cdnhttps 33342 bytes f03e5a3bf534f4a738bc350631fd05bd only different sourceMappingURL December 24, 2015 @ 07:33
Google 33303 bytes f03e5a3bf534f4a738bc350631fd05bd only different sourceMappingURL April 30, 2015 @ 19:52
jsdelivr 33300 bytes f03e5a3bf534f4a738bc350631fd05bd only different sourceMappingURL May 7, 2015 @ 11:21

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
32138 bytes -1 byte zopfli --i1000000 --mls2048 --bsr11 --lazy --ohh October 21, 2015 @ 21:53
32139 bytes -2 bytes zopfli --i100000 --mls2048 --bsr11 --lazy --ohh September 2, 2015 @ 02:52
32141 bytes -5 bytes zopfli --i10000 --mls2048 --bsr11 --lazy --ohh September 1, 2015 @ 21:29
32146 bytes -3 bytes zopfli --i1000 --mls2048 --bsr11 --lazy --ohh September 1, 2015 @ 20:40
32149 bytes zopfli --i100 --mls2048 --bsr12 --lazy --ohh September 1, 2015 @ 20:27

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
32153 32151 32153 32152 32153 32150 32150 32149 32152 32152 32153 32150 32143 32155 32158
32154 32151 32155 32154 32153 32154 32155 32155 32146 32144 32146 32144 32145 32146 32144
32150 32149 32150 32150 32148 32148 32150 32153 32149 32151 32138 32146 32147 32147 32152
32150 32155 32151 32150 32149 32150 32153 32149 32147 32150 32142 32144 32138 32147 32152
32153 32148 32150 32150 32153 32151 32150 32149 32152 32152 32138 32144 32140 32147 32151
32147 32155 32150 32150 32149 32150 32156 32152 32150 32150 32148 32145 32145 32149 32152
32154 32149 32150 32149 32149 32150 32153 32152 32150 32150 32138 32145 32147 32147 32151
32148 32155 32152 32149 32149 32150 32149 32149 32151 32153 32138 32149 32147 32147 32152
32153 32153 32154 32153 32149 32149 32150 32153 32153 32149 32141 32148 32146 32149 32153
32155 32156 32148 32151 32149 32149 32151 32157 32150 32149 32140 32148 32147 32145 32153
32155 32147 32149 32150 32149 32150 32156 32157 32149 32148 32138 32145 32147 32143 32152
32149 32148 32149 32149 32150 32149 32154 32158 32151 32149 32142 32147 32139 32148 32151
32149 32147 32149 32149 32149 32149 32157 32148 32150 32148 32138 32147 32147 32147 32153
32153 32149 32150 32150 32149 32150 32153 32149 32152 32151 32138 32141 32147 32147 32154
32153 32155 32149 32149 32149 32150 32153 32158 32149 32148 32141 32144 32147 32149 32151
32151 32149 32150 32149 32149 32150 32157 32156 32151 32148 32141 32145 32147 32143 32151
32155 32154 32151 32150 32149 32149 32153 32152 32151 32148 32142 32140 32146 32149 32152
32152 32149 32150 32149 32149 32149 32153 32149 32151 32152 32141 32144 32146 32148 32155
32153 32155 32151 32152 32149 32149 32153 32151 32150 32148 32142 32147 32147 32149 32149
32156 32156 32150 32149 32149 32149 32156 32150 32152 32140 32142 32147 32146 32147 32153
32150 32147 32154 32150 32149 32149 32154 32150 32150 32152 32138 32145 32147 32147 32153
32152 32149 32148 32151 32147 32152 32149 32149 32150 32148 32138 32147 32147 32148 32152
32149 32154 32150 32152 32148 32157 32156 32149 32152 32148 32141 32147 32144 32147 32151

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 32149 bytes 100%
1,000 32144 bytes -5 bytes 100%
10,000 32141 bytes -3 bytes 100%
100,000 32139 bytes -2 bytes 4.64%
1,000,000 32138 bytes -1 byte 2.90%
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
32239 bytes +101 bytes (+0.31%) +82 bytes
32238 bytes +100 bytes (+0.31%) +81 bytes
32164 bytes +26 bytes (+0.08%) +7 bytes
32157 bytes +19 bytes (+0.06%)
32170 bytes +32 bytes (+0.10%) +13 bytes
32218 bytes +80 bytes (+0.25%) +61 bytes
32261 bytes +123 bytes (+0.38%) +104 bytes
32289 bytes +151 bytes (+0.47%) +132 bytes
32318 bytes +180 bytes (+0.56%) +161 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 26297 bytes -5841 bytes (-18.17%)
RAR (proprietary) RAR rar a -m5 -md64m -mc63:128t -mt1 27069 bytes -5069 bytes (-15.77%)
PPMd (Wikipedia) 7zip 7za a -mx=9 -m0=ppmd 28777 bytes -3361 bytes (-10.46%)
Brotli (Wikipedia) brotli brotli -q 11 29933 bytes -2205 bytes (-6.86%)
Burrows-Wheeler transform (Wikipedia) bzip2 bzip2 -9 30268 bytes -1870 bytes (-5.82%)
LZMA2 (Wikipedia) xz xz -9 31052 bytes -1086 bytes (-3.38%)
Zstandard (Wikipedia) zstd zstd -19 31678 bytes -460 bytes (-1.43%)

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