lodash 4.17.3 - as small as it gets (near-perfect GZIP compression)

Choose a version:

The original file has 539618 bytes (527.0k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 72781 bytes (71.1k, 13%).

After GZIP compression these minified files vary in size:

Boot	28721 bytes (28.0k)	CDN
cdnjs	25597 bytes (25.0k)	CDN
unpkg	24267 bytes (23.7k)	CDN
gzip -6 (default)	24219 bytes (23.7k)	local copy
jsdelivr	24160 bytes (23.6k)	CDN
gzip -9	24156 bytes (23.6k)	local copy
7zip -mx=9 -tgzip	23347 bytes (22.8k)	local copy
libdeflate -12	23319 bytes (22.8k)	local copy
zultra	23314 bytes (22.8k)	local copy
kzip -s0 -rn -b3	23243 bytes (22.7k)	local copy
pigz -11 -n	23211 bytes (22.7k)	local copy
Zopfli	23177 bytes (22.6k)	local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/lodash/lodash-4.17.3.min.js (or via HTTPS)

You will automatically get the smallest lodash 4.17.3 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 983 bytes by using my lodash 4.17.3 Zopfli version instead of the best available CDN (4.24% smaller than jsdelivr, 23177 vs. 24160 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 --i1000000 --mb8 --mls2048 --bsr23 --lazy --ohh

(found December 26, 2016)

Description	Value	Parameter
iterations	1000000	--i1000000
maximum blocks	8	--mb8
maximum length score	2048	--mls2048
block splitting recursion	23	--bsr23
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/4.17.3/dist/lodash.min.js --location | md5sum
77b6577e047c3a4c8f5969deabfc1368 -
curl --silent --compressed https://minime.stephan-brumme.com/files/lodash/lodash-4.17.3.min.zopfli.js.gz | md5sum
77b6577e047c3a4c8f5969deabfc1368 -

SHA1:
curl --silent --compressed https://raw.githubusercontent.com/lodash/lodash/4.17.3/dist/lodash.min.js --location | sha1sum
23a29bee6b653dacf36848c5d9c66db0c0bf7faf -
curl --silent --compressed https://minime.stephan-brumme.com/files/lodash/lodash-4.17.3.min.zopfli.js.gz | sha1sum
23a29bee6b653dacf36848c5d9c66db0c0bf7faf -

These CDNs send you the original file:

CDN	Size (compressed)	MD5 (uncompressed)	Timestamp
unpkg	24267 bytes	77b6577e047c3a4c8f5969deabfc1368	December 26, 2016 @ 07:34
jsdelivr	24160 bytes	77b6577e047c3a4c8f5969deabfc1368	(invalid)

And some CDNs send you a different file:

CDN	Size (compressed)	MD5 (uncompressed)	Comment / Diff	Timestamp
Boot	28721 bytes	44dc256591a82b3ad4bc54e2803e7988	< /** < * @license < * Lodash lodash.com/license \| Underscore.js 1.8.3 undersc [...] < */ < ;(function(){function n(n,t){return n.set(t[0],t[1]),n}fun [...] < return n}function o(n,t){for(var r=-1,e=null==n?0:n.length [...] < return n}function h(n,t,r,e){var u=-1,i=null==n?0:n.length [...] < --r;for(var e=n.length;++r<e;)if(n[r]===t){n=r;break n}n=- [...] < return n}function k(n,t){for(var r,e=-1,u=n.length;++e<u;) [...] < return"\\"+Tn[n]}function L(n){var t=-1,r=Array(n.size);re [...] [...]	(invalid)
cdnjs	25597 bytes	44dc256591a82b3ad4bc54e2803e7988	< /** < * @license < * Lodash lodash.com/license \| Underscore.js 1.8.3 undersc [...] < */ < ;(function(){function n(n,t){return n.set(t[0],t[1]),n}fun [...] < return n}function o(n,t){for(var r=-1,e=null==n?0:n.length [...] < return n}function h(n,t,r,e){var u=-1,i=null==n?0:n.length [...] < --r;for(var e=n.length;++r<e;)if(n[r]===t){n=r;break n}n=- [...] < return n}function k(n,t){for(var r,e=-1,u=n.length;++e<u;) [...] < return"\\"+Tn[n]}function L(n){var t=-1,r=Array(n.size);re [...] [...]	(invalid)

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
23177 bytes	-2 bytes	zopfli --i1000000 --mls2048 --bsr23 --lazy --ohh	December 26, 2016 @ 21:16
23179 bytes	-1 byte	zopfli --i100000 --mls2048 --bsr23 --lazy --ohh	December 26, 2016 @ 09:23
23180 bytes	-3 bytes	zopfli --i100000 --mls1024 --bsr18 --lazy --ohh	December 26, 2016 @ 08:24
23183 bytes	-1 byte	zopfli --i10000 --mls1024 --bsr18 --lazy --ohh	December 26, 2016 @ 07:50
23184 bytes	-1 byte	zopfli --i1000 --mls2048 --bsr15 --lazy --ohh	December 26, 2016 @ 07:44
23185 bytes	-5 bytes	zopfli --i1000 --mls32 --bsr40 --lazy --ohh	December 26, 2016 @ 07:43
23190 bytes	–	zopfli --i100 --mls4096 --bsr14 --lazy --ohh	December 26, 2016 @ 07:37

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 @ 12:47.

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
2	23235	23236	23233	23231	23229	23229	23222	23224	23225	23229	23233	23226	23230	23235	23230
4	23205	23222	23218	23221	23221	23203	23204	23205	23202	23203	23206	23206	23202	23234	23205
6	23207	23188	23192	23203	23193	23192	23194	23196	23196	23184	23187	23210	23187	23192	23197
7	23193	23184	23192	23196	23192	23192	23202	23202	23202	23195	23184	23187	23212	23189	23189
8	23192	23194	23193	23189	23207	23194	23189	23205	23202	23194	23180	23204	23191	23208	23190
9	23191	23193	23193	23190	23184	23192	23194	23202	23193	23190	23193	23207	23194	23200	23215
10	23193	23191	23196	23191	23205	23197	23194	23201	23200	23202	23205	23192	23184	23199	23192
11	23192	23185	23184	23190	23184	23206	23193	23205	23191	23191	23177	23184	23192	23193	23205
12	23190	23187	23192	23212	23191	23194	23194	23190	23192	23192	23186	23194	23191	23199	23190
13	23211	23204	23183	23201	23221	23194	23208	23203	23203	23183	23192	23205	23193	23208	23204
14	23202	23193	23196	23190	23191	23196	23194	23194	23195	23192	23190	23183	23191	23199	23188
15	23193	23193	23191	23189	23191	23192	23202	23203	23191	23191	23181	23196	23200	23180	23192
16	23202	23201	23202	23196	23185	23194	23187	23200	23188	23193	23185	23196	23192	23190	23189
17	23191	23192	23192	23197	23192	23192	23185	23194	23192	23193	23184	23195	23192	23208	23190
18	23191	23192	23192	23190	23190	23192	23185	23204	23193	23180	23195	23197	23193	23206	23193
19	23193	23185	23191	23191	23202	23193	23202	23202	23192	23196	23194	23197	23192	23207	23190
20	23192	23193	23191	23189	23200	23194	23194	23202	23196	23193	23184	23206	23201	23212	23190
21	23194	23194	23193	23229	23192	23195	23192	23195	23196	23200	23184	23196	23192	23190	23192
22	23204	23194	23193	23199	23202	23194	23194	23190	23191	23180	23188	23192	23192	23192	23189
23	23191	23182	23191	23188	23193	23203	23195	23202	23191	23193	23177	23198	23193	23201	23192
25	23193	23194	23191	23243	23192	23194	23194	23203	23202	23183	23180	23209	23190	23201	23191
30	23191	23183	23194	23191	23192	23194	23195	23191	23192	23198	23184	23202	23191	23200	23189
40	23190	23203	23194	23214	23183	23195	23195	23193	23193	23195	23185	23206	23194	23206	23192

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	23190 bytes	–	100%
1,000	23184 bytes	-6 bytes	100%
10,000	23180 bytes	-4 bytes	100%
100,000	23179 bytes	-1 byte	2.61%
1,000,000	23177 bytes	-2 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
(any)	23266 bytes	+89 bytes (+0.38%)	+23 bytes
1	23432 bytes	+255 bytes (+1.10%)	+189 bytes
2	23308 bytes	+131 bytes (+0.57%)	+65 bytes
3	23243 bytes	+66 bytes (+0.28%)	–
4	23268 bytes	+91 bytes (+0.39%)	+25 bytes
5	23277 bytes	+100 bytes (+0.43%)	+34 bytes
6	23275 bytes	+98 bytes (+0.42%)	+32 bytes
7	23295 bytes	+118 bytes (+0.51%)	+52 bytes
8	23317 bytes	+140 bytes (+0.60%)	+74 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	19446 bytes	-3731 bytes (-16.10%)
RAR (proprietary)	RAR	rar a -m5 -md64m -mc63:128t -mt1	20104 bytes	-3073 bytes (-13.26%)
PPMd (Wikipedia)	7zip	7za a -mx=9 -m0=ppmd	20928 bytes	-2249 bytes (-9.70%)
Brotli (Wikipedia)	brotli	brotli -q 11	21665 bytes	-1512 bytes (-6.52%)
LZMA2 (Wikipedia)	xz	xz -9	22188 bytes	-989 bytes (-4.27%)
Burrows-Wheeler transform (Wikipedia)	bzip2	bzip2 -9	22468 bytes	-709 bytes (-3.06%)
Zstandard (Wikipedia)	zstd	zstd -19	23038 bytes	-139 bytes (-0.60%)

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 2025.
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.