Choose a version:
48% The original file has 513866 bytes (501.8k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 247428 bytes (241.6k, 48%).

After GZIP compression these minified files vary in size:
unpkg
  93424 bytes (91.2k)
CDN
Boot
  81790 bytes (79.9k)
CDN
cdnjs
  81790 bytes (79.9k)
CDN
gzip -6 (default)
  81142 bytes (79.2k)
local copy
gzip -9
  80827 bytes (78.9k)
local copy
libdeflate -12
  77509 bytes (75.7k)
local copy
7zip -mx=9 -tgzip
  77134 bytes (75.3k)
local copy
kzip -s0 -rn -b8
  76898 bytes (75.1k)
local copy
zultra
  76807 bytes (75.0k)
local copy
pigz -11 -n
  76691 bytes (74.9k)
local copy
Zopfli
  76640 bytes (74.8k)
local copy
Zopfli (defluff)
  76639 bytes (74.8k)
local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/d3/d3-5.14.1.min.js (or via HTTPS)

You will automatically get the smallest D3 5.14.1 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 5150 bytes by using my D3 5.14.1 Zopfli version instead of the best available CDN (6.72% smaller than cdnjs, 76640 vs. 81790 bytes):
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 --mls4096 --bsr23 --lazy --ohh

(found November 21, 2019)
Description Value Parameter
iterations 1000000  --i1000000
maximum blocks 8  --mb8
maximum length score 4096  --mls4096
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

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 (76639 bytes).

Verify file integrity

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

MD5:
curl --silent --compressed https://raw.githubusercontent.com/mbostock/d3/v5.14.1/d3.zip --location | md5sum
e231b7eb4454fa7f3d1ef4ebe222a54d  -
curl --silent --compressed https://minime.stephan-brumme.com/files/d3/d3-5.14.1.min.zopfli.js.gz | md5sum
e231b7eb4454fa7f3d1ef4ebe222a54d  -

SHA1:
curl --silent --compressed https://raw.githubusercontent.com/mbostock/d3/v5.14.1/d3.zip --location | sha1sum
4a79d27130245bc9b8252eb715420c7cd4197e02  -
curl --silent --compressed https://minime.stephan-brumme.com/files/d3/d3-5.14.1.min.zopfli.js.gz | sha1sum
4a79d27130245bc9b8252eb715420c7cd4197e02  -

All listed CDNs deliver identical contents:
CDN Size (compressed) MD5 (uncompressed) Timestamp
unpkg 93424 bytes e231b7eb4454fa7f3d1ef4ebe222a54d (invalid)
Boot 81790 bytes e231b7eb4454fa7f3d1ef4ebe222a54d November 27, 2019 @ 19:31
cdnjs 81790 bytes e231b7eb4454fa7f3d1ef4ebe222a54d November 27, 2019 @ 19:31

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

Other Versions

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

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
76640 bytes -5 bytes zopfli --i1000000 --mls4096 --bsr23 --lazy --ohh November 21, 2019 @ 03:22
76645 bytes -7 bytes zopfli --i100000 --mls4096 --bsr23 --lazy --ohh November 20, 2019 @ 14:13
76652 bytes -3 bytes zopfli --i10000 --mls4096 --bsr23 --lazy --ohh November 19, 2019 @ 18:25
76655 bytes -6 bytes zopfli --i10000 --mls4096 --bsr12 --lazy --ohh November 19, 2019 @ 15:52
76661 bytes -7 bytes zopfli --i1000 --mls4096 --bsr23 --lazy --ohh November 19, 2019 @ 12:00
76668 bytes -26 bytes zopfli --i1000 --mls4096 --bsr11 --lazy --ohh November 19, 2019 @ 11:56
76694 bytes zopfli --i100 --mls4096 --bsr12 --lazy --ohh November 19, 2019 @ 11:15

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 @ 12:54.

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
77036 77027 77105 77090 77101 77107 77115 77091 77215 77229 77227 77239 77028 77045 76835
76724 76880 76737 76907 76739 76742 76743 76926 77136 76924 76887 76782 76840 77014 76871
76863 76997 76980 76974 76993 76880 76670 76864 76870 76880 76889 76677 76823 76829 76838
76770 76873 76886 76888 76879 76679 76864 76872 76864 76883 76927 76694 76821 76680 76870
76884 76883 76979 76738 76738 76738 76967 76959 76970 77007 77045 76679 76839 76919 76855
77001 76999 77006 76675 76867 76675 76875 76872 76842 76889 76846 76706 76874 76916 76868
76673 76675 76662 76849 76992 76669 76873 76864 76863 76885 76853 76672 76671 76881 76869
77010 76982 76991 76990 76990 76670 76870 76867 76849 76845 76847 76660 76686 76808 76843
76679 76664 76995 76853 76972 76669 76865 76868 76870 76889 76853 76647 76821 76738 76842
76987 76977 76856 76676 76992 76671 76865 76881 76867 76886 76885 76692 76813 76815 76831
76979 76848 76872 76670 76878 76673 76866 76871 76868 76891 76873 76683 76682 76843 76843
76862 76981 76879 76672 76876 76671 76863 76871 76863 76885 76922 76677 76811 76885 76843
76971 76672 76877 76870 76989 76877 76865 76866 76869 76893 76876 76689 76823 76916 76842
76971 76991 76994 77090 76677 76784 76872 76867 76865 76882 76894 76675 76813 76837 76847
76882 76999 76978 76875 76992 76670 76866 76872 76865 76887 76880 76683 76819 76836 76844
76988 76994 76994 76661 76876 76966 76868 76963 76870 76885 76878 76676 76820 76882 76908
77003 76668 76871 76868 76848 76670 76866 76863 76851 76883 76879 76675 76808 76818 76833
76995 76991 76993 76995 76994 76670 76869 76866 76873 76881 76881 76670 76825 76886 76847
77004 76858 76995 76988 76998 76673 76868 76868 76872 76891 76857 76670 76818 76884 76844
76990 76988 76995 76978 76877 76674 76863 76866 76868 76886 76854 76640 76814 76882 76822
76977 76980 76994 76657 76994 76672 76865 76866 76870 76886 76879 76685 76820 76891 76840
76998 76988 76976 76666 76876 76876 76868 76868 76867 76885 76858 76848 76814 76671 76841
76975 76857 76984 76867 76992 76673 76866 76869 76863 76880 76877 76675 76806 76708 76827

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 76694 bytes 100%
1,000 76661 bytes -33 bytes 100%
10,000 76652 bytes -9 bytes 100%
100,000 76645 bytes -7 bytes 0.58%
1,000,000 76640 bytes -5 bytes 0.29%
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
77064 bytes +424 bytes (+0.55%) +166 bytes
78432 bytes +1792 bytes (+2.34%) +1534 bytes
78319 bytes +1679 bytes (+2.19%) +1421 bytes
77066 bytes +426 bytes (+0.56%) +168 bytes
77072 bytes +432 bytes (+0.56%) +174 bytes
77066 bytes +426 bytes (+0.56%) +168 bytes
77033 bytes +393 bytes (+0.51%) +135 bytes
76981 bytes +341 bytes (+0.44%) +83 bytes
76898 bytes +258 bytes (+0.34%)

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 60292 bytes -16348 bytes (-21.33%)
RAR (proprietary) RAR rar a -m5 -md64m -mc63:128t -mt1 67109 bytes -9531 bytes (-12.44%)
LZMA2 (Wikipedia) xz xz -9 67996 bytes -8644 bytes (-11.28%)
Brotli (Wikipedia) brotli brotli -q 11 68139 bytes -8501 bytes (-11.09%)
PPMd (Wikipedia) 7zip 7za a -mx=9 -m0=ppmd 70145 bytes -6495 bytes (-8.47%)
Zstandard (Wikipedia) zstd zstd -19 73453 bytes -3187 bytes (-4.16%)
Burrows-Wheeler transform (Wikipedia) bzip2 bzip2 -9 76178 bytes -462 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):


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 2020.
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.