lodash 4.15.0 - as small as it gets (near-perfect GZIP compression)

Choose a version:

The original file has 527130 bytes (514.8k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 70686 bytes (69.0k, 13%).

After GZIP compression these minified files vary in size:

Boot	27651 bytes (27.0k)	CDN
cdnjs	24768 bytes (24.2k)	CDN
gzip -6 (default)	23474 bytes (22.9k)	local copy
unpkg	23421 bytes (22.9k)	CDN
jsdelivr	23412 bytes (22.9k)	CDN
gzip -9	23401 bytes (22.9k)	local copy
libdeflate -12	22724 bytes (22.2k)	local copy
7zip -mx=9 -tgzip	22630 bytes (22.1k)	local copy
zultra	22610 bytes (22.1k)	local copy
kzip -s0 -rn -b5	22597 bytes (22.1k)	local copy
pigz -11 -n	22552 bytes (22.0k)	local copy
Zopfli	22500 bytes (22.0k)	local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/lodash/lodash-4.15.0.min.js (or via HTTPS)

You will automatically get the smallest lodash 4.15.0 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 912 bytes by using my lodash 4.15.0 Zopfli version instead of the best available CDN (4.05% smaller than jsdelivr, 22500 vs. 23412 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 --mls512 --bsr20 --lazy --ohh

(found August 15, 2016)

Description	Value	Parameter
iterations	1000000	--i1000000
maximum blocks	8	--mb8
maximum length score	512	--mls512
block splitting recursion	20	--bsr20
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/4.15.0/dist/lodash.min.js --location | md5sum
ae82a6e49d72ce2e21b5a30d0fc3e864 -
curl --silent --compressed https://minime.stephan-brumme.com/files/lodash/lodash-4.15.0.min.zopfli.js.gz | md5sum
ae82a6e49d72ce2e21b5a30d0fc3e864 -

SHA1:
curl --silent --compressed https://raw.githubusercontent.com/lodash/lodash/4.15.0/dist/lodash.min.js --location | sha1sum
3bb5844aee605dc8debc6cdac659093b86fa10b1 -
curl --silent --compressed https://minime.stephan-brumme.com/files/lodash/lodash-4.15.0.min.zopfli.js.gz | sha1sum
3bb5844aee605dc8debc6cdac659093b86fa10b1 -

These CDNs send you the original file:

CDN	Size (compressed)	MD5 (uncompressed)	Timestamp
unpkg	23421 bytes	ae82a6e49d72ce2e21b5a30d0fc3e864	August 12, 2016 @ 18:56
jsdelivr	23412 bytes	ae82a6e49d72ce2e21b5a30d0fc3e864	(invalid)

And some CDNs send you a different file:

CDN	Size (compressed)	MD5 (uncompressed)	Comment / Diff	Timestamp
Boot	27651 bytes	83159a4503e660b94724ba2250ebc564	< /** < * @license < * lodash lodash.com/license \| Underscore.js 1.8.3 undersc [...] < */ < ;(function(){function t(t,n){return t.set(n[0],n[1]),t}fun [...] < return t}function i(t,n){for(var r=-1,e=t?t.length:0;++r<e [...] < var u=-1,o=t?t.length:0;for(e&&o&&(r=t[++u]);++u<o;)r=n(r, [...] < return-1}function y(t,n,r,e){--r;for(var u=t.length;++r<u; [...] < }return r}function E(t,n){for(var r=-1,e=Array(t);++r<t;)e [...] < n=!!(t+"")}catch(t){}return n}function U(t){var n=-1,r=Arr [...] [...]	August 13, 2016 @ 04:48
cdnjs	24768 bytes	83159a4503e660b94724ba2250ebc564	< /** < * @license < * lodash lodash.com/license \| Underscore.js 1.8.3 undersc [...] < */ < ;(function(){function t(t,n){return t.set(n[0],n[1]),t}fun [...] < return t}function i(t,n){for(var r=-1,e=t?t.length:0;++r<e [...] < var u=-1,o=t?t.length:0;for(e&&o&&(r=t[++u]);++u<o;)r=n(r, [...] < return-1}function y(t,n,r,e){--r;for(var u=t.length;++r<u; [...] < }return r}function E(t,n){for(var r=-1,e=Array(t);++r<t;)e [...] < n=!!(t+"")}catch(t){}return n}function U(t){var n=-1,r=Arr [...] [...]	(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
22500 bytes	-2 bytes	zopfli --i1000000 --mls512 --bsr20 --lazy --ohh	August 15, 2016 @ 15:02
22502 bytes	-1 byte	zopfli --i1000000 --mls2048 --bsr7 --lazy --ohh	August 15, 2016 @ 14:33
22503 bytes	-1 byte	zopfli --i100000 --mls512 --bsr20 --lazy --ohh	August 15, 2016 @ 10:32
22504 bytes	-3 bytes	zopfli --i100000 --mls2048 --bsr7 --lazy --ohh	August 12, 2016 @ 19:55
22507 bytes	-1 byte	zopfli --i10000 --mls2048 --bsr7 --lazy --ohh	August 12, 2016 @ 19:11
22508 bytes	-6 bytes	zopfli --i10000 --mls512 --bsr20 --lazy --ohh	August 12, 2016 @ 19:07
22514 bytes	-8 bytes	zopfli --i1000 --mls512 --bsr20 --lazy --ohh	August 12, 2016 @ 19:01
22522 bytes	–	zopfli --i100 --mls512 --bsr20 --lazy --ohh	August 12, 2016 @ 18:58

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 @ 12:52.

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	22573	22573	22568	22570	22569	22559	22563	22568	22570	22543	22545	22546	22559	22552	22556
4	22543	22542	22514	22516	22524	22527	22522	22520	22523	22533	22538	22545	22535	22525	22524
6	22512	22514	22523	22516	22517	22517	22515	22514	22517	22515	22515	22518	22525	22528	22524
7	22517	22527	22524	22517	22516	22522	22512	22528	22528	22532	22502	22528	22524	22535	22521
8	22506	22512	22520	22518	22518	22526	22515	22517	22518	22517	22513	22529	22521	22520	22520
9	22513	22512	22524	22513	22515	22512	22517	22516	22512	22521	22515	22518	22522	22529	22525
10	22514	22514	22520	22516	22513	22518	22515	22511	22515	22520	22522	22518	22521	22523	22503
11	22510	22512	22541	22540	22515	22513	22519	22516	22507	22512	22523	22527	22524	22522	22516
12	22511	22528	22525	22521	22513	22510	22514	22510	22510	22518	22515	22521	22522	22520	22525
13	22512	22513	22522	22520	22519	22514	22512	22512	22514	22516	22515	22516	22522	22533	22530
14	22510	22516	22534	22532	22513	22517	22518	22511	22514	22524	22513	22522	22524	22521	22519
15	22534	22514	22533	22518	22511	22515	22512	22505	22512	22518	22515	22520	22524	22522	22521
16	22515	22521	22512	22517	22512	22526	22512	22512	22515	22520	22526	22521	22523	22524	22517
17	22516	22516	22525	22520	22512	22514	22512	22516	22515	22516	22513	22521	22523	22523	22521
18	22512	22511	22522	22513	22517	22518	22515	22512	22510	22516	22515	22523	22526	22525	22522
19	22512	22513	22511	22514	22511	22524	22518	22511	22514	22510	22521	22521	22514	22524	22515
20	22510	22513	22515	22517	22515	22511	22517	22510	22500	22521	22520	22520	22520	22527	22523
21	22515	22518	22522	22518	22514	22511	22514	22520	22515	22517	22513	22522	22524	22515	22526
22	22512	22510	22518	22516	22514	22520	22516	22517	22519	22518	22522	22518	22528	22530	22515
23	22513	22515	22516	22517	22513	22513	22510	22516	22517	22516	22513	22518	22522	22520	22520
25	22513	22524	22513	22511	22513	22512	22515	22517	22512	22513	22515	22520	22518	22516	22518
30	22510	22515	22520	22517	22516	22512	22511	22513	22520	22516	22516	22518	22526	22518	22519
40	22511	22510	22520	22524	22514	22523	22514	22511	22515	22518	22514	22520	22519	22519	22518

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	22522 bytes	–	100%
1,000	22514 bytes	-8 bytes	100%
10,000	22507 bytes	-7 bytes	100%
100,000	22503 bytes	-4 bytes	1.74%
1,000,000	22500 bytes	-3 bytes	0.87%
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)	22600 bytes	+100 bytes (+0.44%)	+3 bytes
1	22737 bytes	+237 bytes (+1.05%)	+140 bytes
2	22628 bytes	+128 bytes (+0.57%)	+31 bytes
3	22622 bytes	+122 bytes (+0.54%)	+25 bytes
4	22600 bytes	+100 bytes (+0.44%)	+3 bytes
5	22597 bytes	+97 bytes (+0.43%)	–
6	22624 bytes	+124 bytes (+0.55%)	+27 bytes
7	22647 bytes	+147 bytes (+0.65%)	+50 bytes
8	22660 bytes	+160 bytes (+0.71%)	+63 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	18939 bytes	-3561 bytes (-15.83%)
RAR (proprietary)	RAR	rar a -m5 -md64m -mc63:128t -mt1	19497 bytes	-3003 bytes (-13.35%)
PPMd (Wikipedia)	7zip	7za a -mx=9 -m0=ppmd	19848 bytes	-2652 bytes (-11.79%)
Brotli (Wikipedia)	brotli	brotli -q 11	21020 bytes	-1480 bytes (-6.58%)
LZMA2 (Wikipedia)	xz	xz -9	21544 bytes	-956 bytes (-4.25%)
Burrows-Wheeler transform (Wikipedia)	bzip2	bzip2 -9	21858 bytes	-642 bytes (-2.85%)
Zstandard (Wikipedia)	zstd	zstd -19	22409 bytes	-91 bytes (-0.40%)

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.