Choose a version:
13% The original file has 500155 bytes (488.4k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 65797 bytes (64.3k, 13%).

After GZIP compression these minified files vary in size:
Boot
  25806 bytes (25.2k)
 CDN
cdnjs
  22860 bytes (22.3k)
 CDN
gzip -6 (default)
  21810 bytes (21.3k)
 local copy
unpkg
  21806 bytes (21.3k)
 CDN
gzip -9
  21752 bytes (21.2k)
 local copy
libdeflate -12
  21088 bytes (20.6k)
 local copy
7zip -mx=9 -tgzip
  21051 bytes (20.6k)
 local copy
kzip -s0 -rn -b4
  20994 bytes (20.5k)
 local copy
zultra
  20979 bytes (20.5k)
 local copy
pigz -11 -n
  20948 bytes (20.5k)
 local copy
Zopfli
  20918 bytes (20.4k)
 local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/lodash/lodash-4.8.1.min.js (or via HTTPS)

You will automatically get the smallest lodash 4.8.1 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 888 bytes by using my lodash 4.8.1 Zopfli version instead of the best available CDN (4.25% smaller than unpkg, 20918 vs. 21806 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 --i100000 --mb8 --mls4 --bsr6 --lazy --ohh

(found April 13, 2016)
Description Value Parameter
iterations 100000  --i100000
maximum blocks 8  --mb8
maximum length score 4  --mls4
block splitting recursion 6  --bsr6
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/4.8.1/dist/lodash.min.js --location | md5sum
5b2e376ac01fc9f9dcfce203784a32e6  -
curl --silent --compressed https://minime.stephan-brumme.com/files/lodash/lodash-4.8.1.min.zopfli.js.gz | md5sum
5b2e376ac01fc9f9dcfce203784a32e6  -

SHA1:
curl --silent --compressed https://raw.githubusercontent.com/lodash/lodash/4.8.1/dist/lodash.min.js --location | sha1sum
1ab04902274af09c4154554130e6e30b7ab9e1a1  -
curl --silent --compressed https://minime.stephan-brumme.com/files/lodash/lodash-4.8.1.min.zopfli.js.gz | sha1sum
1ab04902274af09c4154554130e6e30b7ab9e1a1  -

CDN Size (compressed) MD5 (uncompressed) Comment / Diff Timestamp
Boot 25806 bytes 0c48c2c572cd18c7ea137f41c2fef1fb < /**
< * @license
< * lodash 4.8.1 (Custom Build) lodash.com/license | Unders [...]
< * Build: `lodash -o ./dist/lodash.js`
< */
< ;(function(){function t(t,n){return t.set(n[0],n[1]),t}fun [...]
< return true}function i(t,n){for(var r=-1,e=t.length,u=0,o= [...]
< var u=t.length;for(e&&u&&(r=t[--u]);u--;)r=n(r,t[u],u,t);r [...]
< return-1}function y(t,n,r,e){--r;for(var u=t.length;++r<u; [...]
< })}function O(t){return function(n){return t(n)}}function [...]
[...]
 May 4, 2016 @ 10:40
cdnjs 22860 bytes e393e93c6d31a2cebf502bb5e231714c < /**
< * @license
< * lodash 4.8.1 (Custom Build) lodash.com/license | Unders [...]
< * Build: `lodash -o ./dist/lodash.js`
< */
< ;(function(){function t(t,n){return t.set(n[0],n[1]),t}fun [...]
< return true}function i(t,n){for(var r=-1,e=t.length,u=0,o= [...]
< var u=t.length;for(e&&u&&(r=t[--u]);u--;)r=n(r,t[u],u,t);r [...]
< return-1}function y(t,n,r,e){--r;for(var u=t.length;++r<u; [...]
< })}function O(t){return function(n){return t(n)}}function [...]
[...]
 (invalid)
unpkg 21806 bytes be07975c82d5ca4e9a4cd321e4f408c8 < * lodash 4.8.1 (Custom Build) lodash.com/license | Unders [...]
> * lodash 4.8.0 (Custom Build) lodash.com/license | Unders [...]
< var n=++gu;return Ze(t)+n},xt.upperCase=xi,xt.upperFirst=j [...]
> var n=++gu;return Ze(t)+n},xt.upperCase=xi,xt.upperFirst=j [...]
 July 11, 2016 @ 16:46

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

Other Versions

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

4.17.21, 4.17.20, 4.17.19, 4.17.18, 4.17.17, 4.17.16, 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
20918 bytes -2 bytes zopfli --i100000 --mls4 --bsr6 --lazy --ohh April 13, 2016 @ 10:03
20920 bytes -1 byte zopfli --i10000 --mls4 --bsr6 --lazy --ohh April 13, 2016 @ 07:24
20921 bytes -2 bytes zopfli --i100000 --mls8192 --bsr17 --lazy --ohh April 12, 2016 @ 13:18
20923 bytes -4 bytes zopfli --i10000 --mls8192 --bsr17 --lazy --ohh April 12, 2016 @ 10:49
20927 bytes -7 bytes zopfli --i1000 --mls8192 --bsr17 --lazy --ohh April 12, 2016 @ 09:22
20934 bytes – zopfli --i100 --mls8192 --bsr17 --lazy --ohh April 12, 2016 @ 03:08

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 @ 12:55.

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 or 100,000.
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 20958 20962 20963 20972 20976 20976 20976 20977 20977 20975 20967 20965 20950 20968 20963
4 20943 20927 20935 20940 20929 20933 20930 20927 20942 20942 20933 20947 20926 20938 20932
6 20936 20918 20947 20941 20934 20933 20936 20930 20943 20946 20945 20934 20936 20940 20951
7 20940 20928 20939 20943 20941 20931 20927 20929 20946 20926 20934 20945 20929 20934 20944
8 20923 20928 20929 20929 20926 20931 20928 20925 20936 20928 20929 20950 20923 20940 20931
9 20929 20930 20933 20943 20927 20928 20928 20921 20944 20932 20932 20945 20925 20953 20930
10 20925 20934 20934 20935 20929 20932 20929 20927 20935 20929 20928 20931 20943 20967 20931
11 20926 20926 20929 20944 20926 20934 20934 20929 20930 20933 20932 20945 20929 20940 20935
12 20928 20938 20937 20945 20928 20930 20927 20928 20947 20927 20933 20929 20931 20932 20931
13 20922 20930 20938 20923 20929 20927 20927 20928 20945 20932 20937 20945 20945 20937 20933
14 20925 20929 20931 20943 20927 20926 20927 20929 20945 20926 20931 20945 20928 20932 20930
15 20929 20930 20927 20945 20926 20931 20927 20930 20946 20929 20940 20937 20930 20934 20936
16 20926 20925 20929 20945 20928 20932 20924 20929 20937 20929 20931 20934 20930 20932 20932
17 20928 20929 20929 20947 20926 20945 20926 20930 20947 20927 20932 20947 20921 20970 20931
18 20927 20922 20929 20943 20927 20932 20928 20930 20945 20925 20936 20932 20931 20972 20938
19 20929 20927 20935 20931 20928 20928 20929 20927 20935 20942 20928 20948 20927 20938 20933
20 20929 20930 20928 20929 20929 20925 20929 20931 20935 20929 20931 20933 20927 20985 20932
21 20927 20930 20936 20933 20925 20927 20928 20928 20933 20918 20928 20933 20929 20938 20933
22 20922 20924 20927 20932 20925 20930 20928 20928 20946 20926 20932 20947 20929 20978 20933
23 20930 20927 20929 20927 20925 20931 20921 20928 20925 20925 20933 20942 20928 20937 20937
25 20928 20937 20937 20943 20929 20927 20927 20929 20938 20922 20930 20944 20925 20938 20937
30 20925 20930 20933 20928 20923 20929 20928 20934 20951 20929 20934 20936 20930 20939 20937
40 20928 20929 20936 20932 20930 20925 20923 20930 20937 20926 20932 20948 20928 20932 20933

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 20934 bytes – 100%
1,000 20924 bytes -10 bytes 100%
10,000 20920 bytes -4 bytes 100%
100,000 20918 bytes -2 bytes 0.87%
1,000,000 – – –
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
(any) 21011 bytes +93 bytes (+0.44%) +17 bytes
1 21071 bytes +153 bytes (+0.73%) +77 bytes
2 21001 bytes +83 bytes (+0.40%) +7 bytes
3 21012 bytes +94 bytes (+0.45%) +18 bytes
4 20994 bytes +76 bytes (+0.36%) –
5 21010 bytes +92 bytes (+0.44%) +16 bytes
6 21033 bytes +115 bytes (+0.55%) +39 bytes
7 21056 bytes +138 bytes (+0.66%) +62 bytes
8 21082 bytes +164 bytes (+0.78%) +88 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 17745 bytes -3173 bytes (-15.17%)
RAR (proprietary) RAR rar a -m5 -md64m -mc63:128t -mt1 18090 bytes -2828 bytes (-13.52%)
PPMd (Wikipedia) 7zip 7za a -mx=9 -m0=ppmd 18406 bytes -2512 bytes (-12.01%)
Brotli (Wikipedia) brotli brotli -q 11 19722 bytes -1196 bytes (-5.72%)
LZMA2 (Wikipedia) xz xz -9 20204 bytes -714 bytes (-3.41%)
Burrows-Wheeler transform (Wikipedia) bzip2 bzip2 -9 20291 bytes -627 bytes (-3.00%)
Zstandard (Wikipedia) zstd zstd -19 20832 bytes -86 bytes (-0.41%)

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):
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 2024.
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.