Choose a version:
27% The original file has 1724578 bytes (1,684.2k) and is available from the project website.
There you can find the official minified version, too, which brings down the size to 459958 bytes (449.2k, 27%).

After GZIP compression these minified files vary in size:
Boot
  145118 bytes (141.7k)
CDN
cdnjs
  119110 bytes (116.3k)
CDN
gzip -6 (default)
  117278 bytes (114.5k)
local copy
gzip -9
  116870 bytes (114.1k)
local copy
cdnhttps
  116769 bytes (114.0k)
CDN
7zip -mx=9 -tgzip
  113093 bytes (110.4k)
local copy
libdeflate -12
  113076 bytes (110.4k)
local copy
pigz -11 -n
  112804 bytes (110.2k)
local copy
kzip -s0 -rn -b5
  112715 bytes (110.1k)
local copy
Zopfli
  112619 bytes (110.0k)
local copy
Zopfli (defluff)
  112618 bytes (110.0k)
local copy

perma-link to the smallest file on my server:
http://minime.stephan-brumme.com/files/ember/ember-2.4.5.min.js (or via HTTPS)

You will automatically get the smallest Ember 2.4.5 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 4150 bytes by using my Ember 2.4.5 Zopfli version instead of the best available CDN (3.68% smaller than cdnhttps, 112619 vs. 116769 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 --i100000 --mb8 --mls32 --bsr14 --lazy --ohh

(found April 14, 2016)
Description Value Parameter
iterations 100000  --i100000
maximum blocks 8  --mb8
maximum length score 32  --mls32
block splitting recursion 14  --bsr14
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 (112618 bytes).

Verify file integrity

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

MD5:
curl --silent --compressed https://builds.emberjs.com/tags/v2.4.5/ember.min.js --location | md5sum
2c20fe7ef178bd686446580f919d933d  -
curl --silent --compressed https://minime.stephan-brumme.com/files/ember/ember-2.4.5.min.zopfli.js.gz | md5sum
2c20fe7ef178bd686446580f919d933d  -

SHA1:
curl --silent --compressed https://builds.emberjs.com/tags/v2.4.5/ember.min.js --location | sha1sum
51b810ba458bce799fe1371dffc6dd8c5e831f4a  -
curl --silent --compressed https://minime.stephan-brumme.com/files/ember/ember-2.4.5.min.zopfli.js.gz | sha1sum
51b810ba458bce799fe1371dffc6dd8c5e831f4a  -

All listed CDNs deliver identical contents:
CDN Size (compressed) MD5 (uncompressed) Timestamp
Boot 145118 bytes 2c20fe7ef178bd686446580f919d933d May 3, 2016 @ 11:51
cdnjs 119110 bytes 2c20fe7ef178bd686446580f919d933d April 11, 2016 @ 23:31
cdnhttps 116769 bytes 2c20fe7ef178bd686446580f919d933d November 22, 2016 @ 16:33

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

Other Versions

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

3.0.0,
2.18.2, 2.18.1, 2.18.0,
2.17.2, 2.17.1, 2.17.0,
2.16.2, 2.16.1, 2.16.0,
2.15.3, 2.15.2, 2.15.1, 2.15.0,
2.14.1, 2.14.0,
2.13.4, 2.13.3, 2.13.2, 2.13.1, 2.13.0,
2.12.2, 2.12.1, 2.12.0,
2.11.3, 2.11.2, 2.11.1, 2.11.0,
2.10.2, 2.10.1, 2.10.0,
2.9.1, 2.9.0,
2.8.3, 2.8.2, 2.8.1, 2.8.0,
2.7.3, 2.7.2, 2.7.1, 2.7.0,
2.6.2, 2.6.1, 2.6.0,
2.5.1, 2.5.0,
2.4.6, 2.4.5, 2.4.4, 2.4.3, 2.4.2, 2.4.1, 2.4.0,
2.3.1, 2.3.0,
2.2.2, 2.2.1, 2.2.0,
2.1.2, 2.1.1, 2.1.0,
2.0.3, 2.0.2, 2.0.1, 2.0.0,
1.13.13, 1.13.12, 1.13.11, 1.13.10, 1.13.9, 1.13.8, 1.13.7, 1.13.6, 1.13.5, 1.13.4, 1.13.3, 1.13.2, 1.13.1, 1.13.0,
1.12.2, 1.12.1, 1.12.0,
1.11.4, 1.11.3, 1.11.2, 1.11.1, 1.11.0,
1.10.1, 1.10.0,
1.9.1, 1.9.0,
1.8.1, 1.8.0,
1.7.1, 1.7.0,
1.6.1, 1.6.0,
1.5.1, 1.5.0,
1.4.0,
1.3.2, 1.3.1, 1.3.0,
1.2.2, 1.2.1, 1.2.0,
1.0.1, 1.0.0

The project site contains an overview how well these versions were compressed.
Other interesting projects are AngularJS, BackboneJS, Bootstrap, D3, Dojo, jQuery, Knockout, lodash, React, Socket.IO, ThreeJS, UnderscoreJS and Vue.

Changelog

Best Zopfli parameters so far:
Size Improvement Parameters Found
112619 bytes -1 byte zopfli --i100000 --mls32 --bsr14 --lazy --ohh April 14, 2016 @ 00:12
112620 bytes -7 bytes zopfli --i100000 --mls64 --bsr12 --lazy --ohh April 12, 2016 @ 19:55
112627 bytes -3 bytes zopfli --i100000 --mls8192 --bsr19 --lazy --ohh April 12, 2016 @ 14:58
112630 bytes -14 bytes zopfli --i10000 --mls8192 --bsr19 --lazy --ohh April 12, 2016 @ 11:49
112644 bytes -23 bytes zopfli --i1000 --mls8192 --bsr19 --lazy --ohh April 12, 2016 @ 11:28
112667 bytes zopfli --i100 --mls8192 --bsr10 --lazy --ohh April 12, 2016 @ 10:09

If there are multiple parameter sets yielding the same compressed size, only the first one found is shown.

Most recent activity on November 22, 2016 @ 16:33.

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
112740 112739 112747 112748 112747 112757 112754 112755 112748 112751 112749 112751 112746 112752 112750
112645 112655 112650 112654 112654 112669 112662 112691 112679 112698 112678 112750 112751 112652 112740
112644 112648 112645 112641 112667 112690 112675 112685 112654 112816 112671 112660 112663 112655 112665
112741 112747 112746 112744 112744 112745 112747 112751 112746 112818 112667 112651 112649 112647 112740
112741 112747 112745 112746 112743 112809 112752 112747 112748 112753 112664 112752 112627 112725 112739
112751 112747 112746 112744 112631 112752 112746 112751 112746 112743 112667 112650 112650 112744 112738
112741 112747 112746 112744 112631 112631 112747 112751 112746 112746 112655 112746 112634 112742 112739
112741 112744 112747 112746 112632 112743 112619 112740 112744 112742 112661 112631 112637 112742 112738
112748 112747 112745 112743 112625 112620 112747 112751 112752 112742 112654 112750 112652 112747 112739
112745 112753 112743 112749 112631 112631 112745 112751 112746 112746 112662 112631 112648 112744 112749
112747 112742 112743 112743 112619 112620 112746 112743 112752 112742 112745 112653 112648 112747 112739
112819 112745 112743 112743 112633 112620 112743 112743 112753 112818 112661 112642 112641 112742 112739
112742 112744 112746 112746 112620 112755 112747 112743 112747 112743 112660 112751 112648 112744 112739
112741 112747 112743 112746 112745 112631 112631 112743 112744 112742 112665 112638 112654 112747 112739
112642 112746 112743 112747 112631 112752 112633 112751 112752 112743 112641 112751 112649 112742 112738
112640 112750 112747 112747 112745 112745 112746 112751 112751 112742 112661 112634 112627 112747 112739
112748 112826 112748 112748 112625 112747 112753 112743 112746 112746 112660 112632 112649 112747 112739
112747 112749 112747 112747 112625 112631 112743 112751 112746 112742 112661 112746 112647 112744 112738
112752 112744 112747 112743 112619 112751 112631 112747 112752 112742 112660 112637 112651 112740 112740
112741 112747 112746 112746 112633 112751 112747 112743 112752 112746 112652 112633 112649 112745 112740
112741 112745 112746 112744 112633 112620 112743 112743 112752 112746 112650 112637 112649 112747 112740
112752 112744 112747 112746 112631 112631 112632 112747 112744 112746 112650 112637 112647 112747 112739
112741 112747 112746 112748 112634 112809 112746 112743 112747 112743 112660 112636 112649 112744 112738

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 112667 bytes 100%
1,000 112638 bytes -29 bytes 100%
10,000 112630 bytes -8 bytes 100%
100,000 112619 bytes -11 bytes 3.77%
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
112826 bytes +207 bytes (+0.18%) +111 bytes
112783 bytes +164 bytes (+0.15%) +68 bytes
112823 bytes +204 bytes (+0.18%) +108 bytes
112849 bytes +230 bytes (+0.20%) +134 bytes
112721 bytes +102 bytes (+0.09%) +6 bytes
112715 bytes +96 bytes (+0.09%)
112746 bytes +127 bytes (+0.11%) +31 bytes
112798 bytes +179 bytes (+0.16%) +83 bytes
112825 bytes +206 bytes (+0.18%) +110 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 - but your browser doesn't support it.
Algorithm Program Parameters Size Compared To Best Zopfli
ZPAQ (Wikipedia) zpaq zpaq -method 69 76775 bytes -35844 bytes (-31.83%)
RAR (proprietary) RAR rar a -m5 -md64m -mc63:128t -mt1 82241 bytes -30378 bytes (-26.97%)
PPMd (Wikipedia) 7zip 7za a -mx=9 -m0=ppmd 88605 bytes -24014 bytes (-21.32%)
Burrows-Wheeler transform (Wikipedia) bzip2 bzip2 -9 93514 bytes -19105 bytes (-16.96%)
Brotli (Wikipedia) brotli brotli -q 11 97846 bytes -14773 bytes (-13.12%)
LZMA2 (Wikipedia) xz xz -9 100036 bytes -12583 bytes (-11.17%)
Zstandard (Wikipedia) zstd zstd -19 102814 bytes -9805 bytes (-8.71%)

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 2018.
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