D3 3.5.5 - as small as it gets (near-perfect GZIP compression)

Choose a version:

The original file has 336396 bytes (328.5k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 151125 bytes (147.6k, 45%).

After GZIP compression these minified files vary in size:

Boot	60914 bytes (59.5k)	CDN
jsdelivr	60914 bytes (59.5k)	CDN
cdnjs	53777 bytes (52.5k)	CDN
unpkg	53491 bytes (52.2k)	CDN
gzip -6 (default)	53359 bytes (52.1k)	local copy
gzip -9	53204 bytes (52.0k)	local copy
libdeflate -12	51520 bytes (50.3k)	local copy
7zip -mx=9 -tgzip	51482 bytes (50.3k)	local copy
zultra	51482 bytes (50.3k)	local copy
pigz -11 -n	51172 bytes (50.0k)	local copy
kzip -s0 -rn -b7	51167 bytes (50.0k)	local copy
Zopfli	51109 bytes (49.9k)	local copy
Zopfli (defluff)	51106 bytes (49.9k)	local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/d3/d3-3.5.5.min.js (or via HTTPS)

You will automatically get the smallest D3 3.5.5 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 2382 bytes by using my D3 3.5.5 Zopfli version instead of the best available CDN (4.66% smaller than unpkg, 51109 vs. 53491 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 --mls32768 --bsr40 --lazy --ohh

(found December 22, 2015)

Description	Value	Parameter
iterations	100000	--i100000
maximum blocks	8	--mb8
maximum length score	32768	--mls32768
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 3 more bytes (51106 bytes).

Download

Verify file integrity

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

MD5:
curl --silent --compressed https://raw.githubusercontent.com/mbostock/d3/v3.5.5/d3.min.js --location | md5sum
5936da7688d010c60aaf8374f90fcc2b -
curl --silent --compressed https://minime.stephan-brumme.com/files/d3/d3-3.5.5.min.zopfli.js.gz | md5sum
5936da7688d010c60aaf8374f90fcc2b -

SHA1:
curl --silent --compressed https://raw.githubusercontent.com/mbostock/d3/v3.5.5/d3.min.js --location | sha1sum
751927cc0f71697c6b6f680192ac84a6d7ff3787 -
curl --silent --compressed https://minime.stephan-brumme.com/files/d3/d3-3.5.5.min.zopfli.js.gz | sha1sum
751927cc0f71697c6b6f680192ac84a6d7ff3787 -

All listed CDNs deliver identical contents:

CDN	Size (compressed)	MD5 (uncompressed)	Timestamp
Boot	60914 bytes	5936da7688d010c60aaf8374f90fcc2b	(invalid)
jsdelivr	60914 bytes	5936da7688d010c60aaf8374f90fcc2b	(invalid)
cdnjs	53777 bytes	5936da7688d010c60aaf8374f90fcc2b	(invalid)
unpkg	53491 bytes	5936da7688d010c60aaf8374f90fcc2b	July 11, 2016 @ 16:30

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

Other Versions

Available D3 versions at minime.stephan-brumme.com:

6.7.0, 6.6.2, 6.6.1, 6.6.0, 6.5.0, 6.4.0, 6.3.1, 6.2.0, 6.1.1, 6.1.0, 6.0.0,
5.16.0, 5.15.1, 5.15.0, 5.14.2, 5.14.1, 5.14.0, 5.13.1, 5.13.0, 5.12.0, 5.11.0, 5.10.1, 5.10.0,
5.9.7, 5.9.6, 5.9.5, 5.9.4, 5.9.3, 5.9.2, 5.9.1, 5.9.0, 5.8.2, 5.8.1, 5.8.0, 5.7.0, 5.6.0, 5.5.0, 5.4.0, 5.3.0, 5.2.0, 5.1.0, 5.0.1, 5.0.0,
4.13.0, 4.12.2, 4.12.1, 4.12.0, 4.11.0, 4.10.2, 4.10.1, 4.10.0,
4.9.1, 4.9.0, 4.8.0, 4.7.4, 4.7.3, 4.7.2, 4.7.1, 4.7.0, 4.6.0, 4.5.0, 4.4.4, 4.4.3, 4.4.2, 4.4.1, 4.4.0, 4.3.0, 4.2.8, 4.2.7, 4.2.6, 4.2.5, 4.2.4, 4.2.3, 4.2.2, 4.2.1, 4.2.0, 4.1.1, 4.1.0, 4.0.0,
3.5.17, 3.5.16, 3.5.15, 3.5.14, 3.5.13, 3.5.12, 3.5.11, 3.5.10, 3.5.9, 3.5.8, 3.5.7, 3.5.6, 3.5.5, 3.5.4, 3.5.3, 3.5.2, 3.5.1, 3.5.0, 3.4.13, 3.4.12, 3.4.11, 3.4.10, 3.4.9, 3.4.8, 3.4.6, 3.4.5, 3.4.4, 3.4.3, 3.4.2, 3.4.1, 3.4.0, 3.3.13, 3.3.12, 3.3.11, 3.3.10, 3.3.9, 3.3.8, 3.3.7, 3.3.6, 3.3.5, 3.3.4, 3.3.3, 3.3.2, 3.3.1, 3.3.0, 3.2.8, 3.2.7, 3.2.6, 3.2.5, 3.2.4, 3.2.3, 3.2.2, 3.2.1, 3.2.0, 3.1.10, 3.1.9, 3.1.8, 3.1.7, 3.1.6, 3.1.5, 3.1.4, 3.1.3, 3.1.2, 3.1.1, 3.1.0, 3.0.8, 3.0.7, 3.0.6, 3.0.5, 3.0.4, 3.0.3, 3.0.2, 3.0.1, 3.0.0

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

Changelog

Best Zopfli parameters so far:

Size	Improvement	Parameters	Found
51109 bytes	-2 bytes	zopfli --i100000 --mls32768 --bsr40 --lazy --ohh	December 22, 2015 @ 17:51
51111 bytes	-6 bytes	zopfli --i10000 --mls32768 --bsr40 --lazy --ohh	October 14, 2015 @ 01:12
51117 bytes	-7 bytes	zopfli --i1000 --mls32768 --bsr40 --lazy --ohh	October 13, 2015 @ 18:37
51124 bytes	-7 bytes	zopfli --i10000 --mls256 --bsr16 --lazy --ohh	September 21, 2015 @ 08:56
51131 bytes	-13 bytes	zopfli --i1000 --mls256 --bsr16 --lazy --ohh	September 19, 2015 @ 00:06
51144 bytes	-5 bytes	zopfli --i1000 --mls256 --bsr12 --lazy --ohh	September 19, 2015 @ 00:04
51149 bytes	–	zopfli --i100 --mls32768 --bsr16 --lazy --ohh	September 18, 2015 @ 20:49

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 @ 13:07.

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	51259	51265	51295	51269	51299	51339	51281	51300	51241	51379	51381	51274	51397	51269	51393
4	51137	51186	51188	51196	51182	51169	51206	51180	51234	51168	51391	51275	51248	51155	51384
6	51187	51206	51213	51248	51238	51175	51256	51196	51149	51143	51226	51262	51230	51155	51387
7	51178	51245	51175	51154	51227	51201	51167	51166	51157	51143	51238	51245	51260	51156	51146
8	51184	51154	51226	51214	51234	51162	51179	51219	51139	51394	51392	51260	51397	51136	51139
9	51197	51230	51225	51318	51231	51154	51216	51161	51252	51166	51230	51246	51383	51136	51166
10	51205	51222	51226	51234	51160	51164	51215	51213	51145	51229	51222	51256	51383	51145	51152
11	51198	51157	51226	51322	51221	51182	51324	51151	51151	51151	51240	51250	51220	51141	51138
12	51200	51224	51147	51325	51237	51173	51241	51140	51154	51149	51239	51260	51236	51157	51136
13	51176	51221	51224	51186	51229	51219	51179	51216	51147	51136	51236	51245	51220	51154	51140
14	51199	51216	51206	51324	51232	51188	51148	51205	51145	51146	51248	51228	51243	51139	51177
15	51182	51219	51163	51213	51235	51149	51166	51203	51153	51153	51233	51253	51396	51149	51135
16	51202	51202	51230	51199	51232	51233	51326	51124	51158	51143	51252	51246	51243	51149	51132
17	51226	51151	51226	51323	51232	51241	51326	51138	51142	51153	51249	51246	51236	51141	51148
18	51198	51225	51210	51220	51237	51242	51319	51202	51157	51150	51249	51254	51234	51141	51384
19	51223	51214	51210	51323	51234	51165	51323	51233	51160	51154	51249	51256	51238	51137	51153
20	51225	51222	51225	51323	51232	51238	51233	51163	51154	51148	51249	51251	51242	51136	51142
21	51196	51223	51227	51324	51232	51155	51324	51164	51154	51148	51250	51253	51245	51139	51153
22	51198	51198	51206	51322	51209	51169	51324	51174	51152	51152	51224	51252	51236	51140	51153
23	51206	51211	51215	51151	51237	51242	51200	51165	51153	51145	51248	51248	51243	51142	51139
25	51198	51220	51200	51211	51233	51167	51199	51163	51155	51156	51249	51245	51236	51139	51150
30	51200	51222	51201	51221	51235	51200	51211	51233	51150	51151	51251	51261	51243	51142	51146
40	51184	51223	51211	51233	51231	51242	51324	51123	51155	51151	51253	51250	51385	51142	51109

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	51126 bytes	–	100%
1,000	51117 bytes	-9 bytes	100%
10,000	51111 bytes	-6 bytes	100%
100,000	51109 bytes	-2 bytes	0.29%
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)	51424 bytes	+315 bytes (+0.62%)	+257 bytes
1	51423 bytes	+314 bytes (+0.61%)	+256 bytes
2	51433 bytes	+324 bytes (+0.63%)	+266 bytes
3	51370 bytes	+261 bytes (+0.51%)	+203 bytes
4	51312 bytes	+203 bytes (+0.40%)	+145 bytes
5	51312 bytes	+203 bytes (+0.40%)	+145 bytes
6	51214 bytes	+105 bytes (+0.21%)	+47 bytes
7	51167 bytes	+58 bytes (+0.11%)	–
8	51187 bytes	+78 bytes (+0.15%)	+20 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	40774 bytes	-10335 bytes (-20.22%)
RAR (proprietary)	RAR	rar a -m5 -md64m -mc63:128t -mt1	43401 bytes	-7708 bytes (-15.08%)
PPMd (Wikipedia)	7zip	7za a -mx=9 -m0=ppmd	44444 bytes	-6665 bytes (-13.04%)
Brotli (Wikipedia)	brotli	brotli -q 11	46143 bytes	-4966 bytes (-9.72%)
LZMA2 (Wikipedia)	xz	xz -9	46880 bytes	-4229 bytes (-8.27%)
Burrows-Wheeler transform (Wikipedia)	bzip2	bzip2 -9	48833 bytes	-2276 bytes (-4.45%)
Zstandard (Wikipedia)	zstd	zstd -19	49427 bytes	-1682 bytes (-3.29%)

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.