Choose a version:
14% The original file has 540512 bytes (527.8k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 73261 bytes (71.5k, 14%).

After GZIP compression these minified files vary in size:
unpkg
  28741 bytes (28.1k)
CDN
Boot
  24630 bytes (24.1k)
CDN
cdnjs
  24630 bytes (24.1k)
CDN
gzip -6 (default)
  24434 bytes (23.9k)
local copy
gzip -9
  24365 bytes (23.8k)
local copy
7zip -mx=9 -tgzip
  23534 bytes (23.0k)
local copy
libdeflate -12
  23523 bytes (23.0k)
local copy
kzip -s0 -rn -b3
  23454 bytes (22.9k)
local copy
pigz -11 -n
  23406 bytes (22.9k)
local copy
Zopfli
  23372 bytes (22.8k)
local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/lodash/lodash-4.17.12.min.js (or via HTTPS)

You will automatically get the smallest lodash 4.17.12 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 1258 bytes by using my lodash 4.17.12 Zopfli version instead of the best available CDN (5.38% smaller than cdnjs, 23372 vs. 24630 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 --mls8 --bsr40 --lazy --ohh

(found July 12, 2019)
Description Value Parameter
iterations 1000000  --i1000000
maximum blocks 8  --mb8
maximum length score 8  --mls8
block splitting recursion 40  --bsr40
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://raw.githubusercontent.com/lodash/lodash/4.17.12/dist/lodash.min.js --location | md5sum
c93d9ee36c0416f8f4e1c2264fac05a1  -
curl --silent --compressed https://minime.stephan-brumme.com/files/lodash/lodash-4.17.12.min.zopfli.js.gz | md5sum
c93d9ee36c0416f8f4e1c2264fac05a1  -

SHA1:
curl --silent --compressed https://raw.githubusercontent.com/lodash/lodash/4.17.12/dist/lodash.min.js --location | sha1sum
690728a8dee389664a581c2c3114c37f8d2a2a82  -
curl --silent --compressed https://minime.stephan-brumme.com/files/lodash/lodash-4.17.12.min.zopfli.js.gz | sha1sum
690728a8dee389664a581c2c3114c37f8d2a2a82  -

All listed CDNs deliver identical contents:
CDN Size (compressed) MD5 (uncompressed) Timestamp
unpkg 28741 bytes c93d9ee36c0416f8f4e1c2264fac05a1 (invalid)
Boot 24630 bytes c93d9ee36c0416f8f4e1c2264fac05a1 (invalid)
cdnjs 24630 bytes c93d9ee36c0416f8f4e1c2264fac05a1 (invalid)

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

Other Versions

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

4.17.15, 4.17.14, 4.17.13, 4.17.12, 4.17.11, 4.17.10, 4.17.9, 4.17.5, 4.17.4, 4.17.3, 4.17.2, 4.17.1, 4.17.0, 4.16.6, 4.16.5, 4.16.4, 4.16.3, 4.16.2, 4.16.1, 4.16.0, 4.15.0, 4.14.2, 4.14.1, 4.14.0, 4.13.1, 4.13.0, 4.12.0, 4.11.2, 4.11.1, 4.11.0, 4.10.0,
4.9.0, 4.8.2, 4.8.1, 4.8.0, 4.7.0, 4.6.1, 4.6.0, 4.5.1, 4.5.0, 4.4.0, 4.3.0, 4.2.1, 4.2.0, 4.1.0, 4.0.1, 4.0.0

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

Changelog

Best Zopfli parameters so far:
Size Improvement Parameters Found
23372 bytes -1 byte zopfli --i1000000 --mls8 --bsr40 --lazy --ohh July 12, 2019 @ 15:06
23373 bytes -1 byte zopfli --i100000 --mls8 --bsr40 --lazy --ohh July 12, 2019 @ 11:08
23374 bytes -3 bytes zopfli --i10000 --mls8 --bsr40 --lazy --ohh July 11, 2019 @ 21:13
23377 bytes -9 bytes zopfli --i1000 --mls8 --bsr16 --lazy --ohh July 11, 2019 @ 15:44
23386 bytes -1 byte zopfli --i1000 --mls512 --bsr12 --lazy --ohh July 11, 2019 @ 15:34
23387 bytes -2 bytes zopfli --i1000 --mls16 --bsr19 --lazy --ohh July 11, 2019 @ 15:31
23389 bytes -1 byte zopfli --i1000 --mls32768 --bsr10 --lazy --ohh July 11, 2019 @ 15:30
23390 bytes zopfli --i100 --mls8 --bsr16 --lazy --ohh July 11, 2019 @ 15:18

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

Most recent activity on July 12, 2019 @ 15:06.

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
23427 23427 23415 23417 23417 23418 23416 23415 23417 23473 23427 23431 23410 23429 23417
23407 23407 23416 23409 23409 23409 23413 23410 23420 23407 23397 23408 23404 23400 23410
23384 23386 23384 23401 23385 23394 23389 23396 23403 23384 23450 23406 23405 23384 23402
23386 23386 23385 23392 23385 23395 23387 23399 23401 23396 23435 23400 23410 23387 23407
23386 23386 23387 23388 23387 23396 23389 23384 23384 23436 23401 23407 23406 23384 23385
23387 23387 23383 23393 23385 23396 23387 23385 23423 23384 23396 23446 23403 23385 23384
23388 23390 23393 23384 23385 23388 23387 23388 23385 23384 23436 23400 23406 23383 23386
23387 23386 23401 23400 23386 23405 23404 23413 23407 23395 23401 23385 23402 23403 23411
23384 23386 23393 23385 23385 23385 23389 23394 23384 23383 23433 23401 23403 23402 23387
23386 23396 23397 23399 23385 23385 23396 23399 23405 23383 23397 23401 23404 23384 23407
23387 23386 23386 23385 23385 23394 23385 23385 23407 23402 23396 23405 23401 23419 23404
23393 23391 23388 23387 23385 23386 23385 23386 23403 23395 23396 23405 23402 23385 23408
23404 23384 23374 23404 23384 23385 23387 23402 23385 23385 23433 23445 23402 23385 23384
23386 23385 23387 23385 23384 23388 23385 23398 23402 23402 23385 23405 23417 23402 23384
23386 23386 23386 23400 23385 23394 23388 23399 23408 23396 23403 23405 23402 23385 23385
23387 23384 23385 23386 23388 23386 23400 23398 23402 23385 23435 23412 23405 23385 23387
23390 23384 23387 23398 23387 23386 23388 23401 23401 23437 23401 23446 23403 23385 23386
23387 23384 23392 23399 23385 23397 23385 23403 23402 23401 23387 23403 23403 23385 23385
23389 23384 23374 23400 23388 23385 23384 23385 23385 23399 23435 23403 23406 23419 23384
23387 23385 23387 23389 23387 23396 23389 23384 23384 23399 23385 23402 23404 23385 23384
23385 23386 23391 23390 23402 23386 23391 23398 23385 23402 23401 23405 23412 23384 23384
23386 23389 23387 23387 23385 23386 23386 23385 23383 23383 23402 23402 23403 23419 23387
23404 23387 23372 23399 23387 23395 23387 23386 23387 23403 23384 23394 23405 23384 23387

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 23390 bytes 100%
1,000 23377 bytes -13 bytes 100%
10,000 23374 bytes -3 bytes 100%
100,000 23373 bytes -1 byte 0.87%
1,000,000 23372 bytes -1 byte 0.29%
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
23478 bytes +106 bytes (+0.45%) +24 bytes
23626 bytes +254 bytes (+1.09%) +172 bytes
23511 bytes +139 bytes (+0.59%) +57 bytes
23454 bytes +82 bytes (+0.35%)
23475 bytes +103 bytes (+0.44%) +21 bytes
23472 bytes +100 bytes (+0.43%) +18 bytes
23475 bytes +103 bytes (+0.44%) +21 bytes
23497 bytes +125 bytes (+0.53%) +43 bytes
23509 bytes +137 bytes (+0.59%) +55 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 - but your browser doesn't support it.
Algorithm Program Parameters Size Compared To Best Zopfli
ZPAQ (Wikipedia) zpaq zpaq -method 69 19624 bytes -3748 bytes (-16.04%)
RAR (proprietary) RAR rar a -m5 -md64m -mc63:128t -mt1 20262 bytes -3110 bytes (-13.31%)
PPMd (Wikipedia) 7zip 7za a -mx=9 -m0=ppmd 21078 bytes -2294 bytes (-9.82%)
Brotli (Wikipedia) brotli brotli -q 11 21809 bytes -1563 bytes (-6.69%)
LZMA2 (Wikipedia) xz xz -9 22340 bytes -1032 bytes (-4.42%)
Burrows-Wheeler transform (Wikipedia) bzip2 bzip2 -9 22594 bytes -778 bytes (-3.33%)
Zstandard (Wikipedia) zstd zstd -19 23100 bytes -272 bytes (-1.16%)

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 2019.
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