lodash 4.17.0 - as small as it gets (near-perfect GZIP compression)

Choose a version:

The original file has 538946 bytes (526.3k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 72779 bytes (71.1k, 14%).

After GZIP compression these minified files vary in size:

Boot	28744 bytes (28.1k)	CDN
cdnjs	25622 bytes (25.0k)	CDN
unpkg	24298 bytes (23.7k)	CDN
gzip -6 (default)	24275 bytes (23.7k)	local copy
jsdelivr	24208 bytes (23.6k)	CDN
gzip -9	24201 bytes (23.6k)	local copy
7zip -mx=9 -tgzip	23378 bytes (22.8k)	local copy
zultra	23364 bytes (22.8k)	local copy
libdeflate -12	23352 bytes (22.8k)	local copy
kzip -s0 -rn -b3	23279 bytes (22.7k)	local copy
pigz -11 -n	23249 bytes (22.7k)	local copy
Zopfli	23213 bytes (22.7k)	local copy
Zopfli (defluff)	23212 bytes (22.7k)	local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/lodash/lodash-4.17.0.min.js (or via HTTPS)

You will automatically get the smallest lodash 4.17.0 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 995 bytes by using my lodash 4.17.0 Zopfli version instead of the best available CDN (4.29% smaller than jsdelivr, 23213 vs. 24208 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 --mls2 --bsr40 --lazy --ohh

(found November 14, 2016)

Description	Value	Parameter
iterations	1000000	--i1000000
maximum blocks	8	--mb8
maximum length score	2	--mls2
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

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 (23212 bytes).

Download

Verify file integrity

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

MD5:
curl --silent --compressed https://raw.githubusercontent.com/lodash/lodash/4.17.0/dist/lodash.min.js --location | md5sum
b5663c28f18e04831e8a96e8e17eb849 -
curl --silent --compressed https://minime.stephan-brumme.com/files/lodash/lodash-4.17.0.min.zopfli.js.gz | md5sum
b5663c28f18e04831e8a96e8e17eb849 -

SHA1:
curl --silent --compressed https://raw.githubusercontent.com/lodash/lodash/4.17.0/dist/lodash.min.js --location | sha1sum
199a6a8cbc8f166c4ab24b9e18aaed4b987e0ed1 -
curl --silent --compressed https://minime.stephan-brumme.com/files/lodash/lodash-4.17.0.min.zopfli.js.gz | sha1sum
199a6a8cbc8f166c4ab24b9e18aaed4b987e0ed1 -

These CDNs send you the original file:

CDN	Size (compressed)	MD5 (uncompressed)	Timestamp
unpkg	24298 bytes	b5663c28f18e04831e8a96e8e17eb849	November 14, 2016 @ 10:57
jsdelivr	24208 bytes	b5663c28f18e04831e8a96e8e17eb849	(invalid)

And some CDNs send you a different file:

CDN	Size (compressed)	MD5 (uncompressed)	Comment / Diff	Timestamp
Boot	28744 bytes	2d0b9db73eb24a4e42c8a2f641dcbb0b	< /** < * @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	25622 bytes	2d0b9db73eb24a4e42c8a2f641dcbb0b	< /** < * @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
23213 bytes	-1 byte	zopfli --i1000000 --mls2 --bsr40 --lazy --ohh	November 14, 2016 @ 18:32
23214 bytes	-1 byte	zopfli --i10000 --mls2 --bsr40 --lazy --ohh	November 14, 2016 @ 11:31
23215 bytes	-3 bytes	zopfli --i10000 --mls1024 --bsr7 --lazy --ohh	November 14, 2016 @ 11:10
23218 bytes	-8 bytes	zopfli --i1000 --mls1024 --bsr7 --lazy --ohh	November 14, 2016 @ 11:01
23226 bytes	–	zopfli --i100 --mls1024 --bsr7 --lazy --ohh	November 14, 2016 @ 10:58

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 @ 12:49.

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	23271	23274	23268	23268	23260	23263	23258	23261	23260	23261	23266	23261	23260	23280	23271
4	23256	23253	23251	23287	23259	23240	23260	23239	23239	23241	23242	23247	23239	23252	23244
6	23227	23243	23223	23228	23230	23230	23230	23227	23226	23229	23240	23229	23230	23227	23244
7	23218	23224	23230	23227	23259	23227	23235	23234	23243	23213	23229	23228	23235	23241	23226
8	23227	23227	23227	23228	23235	23245	23231	23239	23234	23246	23230	23233	23231	23242	23239
9	23226	23227	23226	23224	23237	23245	23235	23251	23234	23220	23225	23228	23244	23242	23226
10	23228	23227	23227	23225	23237	23233	23239	23237	23236	23236	23229	23232	23219	23224	23215
11	23225	23213	23229	23225	23230	23230	23219	23229	23233	23216	23243	23244	23244	23241	23226
12	23220	23227	23227	23224	23255	23230	23229	23235	23232	23223	23228	23225	23227	23243	23226
13	23224	23218	23228	23226	23235	23229	23233	23242	23234	23226	23232	23228	23226	23241	23226
14	23226	23213	23227	23225	23236	23231	23226	23231	23232	23216	23229	23228	23235	23223	23237
15	23213	23219	23227	23228	23234	23230	23235	23238	23232	23215	23216	23228	23234	23241	23233
16	23226	23225	23227	23227	23233	23228	23225	23249	23224	23224	23229	23232	23225	23244	23238
17	23218	23227	23227	23225	23233	23229	23231	23230	23235	23226	23217	23228	23243	23241	23234
18	23226	23225	23227	23225	23238	23232	23229	23237	23235	23218	23213	23229	23228	23241	23227
19	23229	23230	23226	23234	23236	23230	23230	23227	23222	23219	23233	23226	23242	23245	23225
20	23218	23227	23228	23225	23237	23231	23234	23234	23235	23216	23216	23227	23227	23241	23225
21	23225	23228	23231	23227	23233	23231	23229	23229	23236	23222	23238	23226	23225	23242	23226
22	23226	23224	23226	23227	23232	23229	23218	23227	23232	23218	23231	23228	23225	23241	23226
23	23227	23226	23227	23225	23238	23230	23236	23236	23233	23221	23213	23229	23228	23241	23226
25	23225	23225	23226	23264	23232	23230	23218	23237	23232	23215	23228	23228	23226	23241	23224
30	23221	23224	23229	23224	23238	23231	23231	23236	23220	23216	23229	23228	23225	23242	23240
40	23213	23218	23228	23224	23237	23230	23230	23238	23234	23225	23230	23226	23227	23227	23242

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	23226 bytes	–	100%
1,000	23218 bytes	-8 bytes	100%
10,000	23214 bytes	-4 bytes	100%
100,000	23214 bytes	–	4.93%
1,000,000	23213 bytes	-1 byte	2.03%
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)	23314 bytes	+101 bytes (+0.44%)	+35 bytes
1	23467 bytes	+254 bytes (+1.09%)	+188 bytes
2	23346 bytes	+133 bytes (+0.57%)	+67 bytes
3	23279 bytes	+66 bytes (+0.28%)	–
4	23301 bytes	+88 bytes (+0.38%)	+22 bytes
5	23304 bytes	+91 bytes (+0.39%)	+25 bytes
6	23307 bytes	+94 bytes (+0.40%)	+28 bytes
7	23327 bytes	+114 bytes (+0.49%)	+48 bytes
8	23354 bytes	+141 bytes (+0.61%)	+75 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	19500 bytes	-3713 bytes (-16.00%)
RAR (proprietary)	RAR	rar a -m5 -md64m -mc63:128t -mt1	20144 bytes	-3069 bytes (-13.22%)
PPMd (Wikipedia)	7zip	7za a -mx=9 -m0=ppmd	20957 bytes	-2256 bytes (-9.72%)
Brotli (Wikipedia)	brotli	brotli -q 11	21684 bytes	-1529 bytes (-6.59%)
LZMA2 (Wikipedia)	xz	xz -9	22204 bytes	-1009 bytes (-4.35%)
Burrows-Wheeler transform (Wikipedia)	bzip2	bzip2 -9	22545 bytes	-668 bytes (-2.88%)
Zstandard (Wikipedia)	zstd	zstd -19	23081 bytes	-132 bytes (-0.57%)

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.