Comparison of layout engines (web typography)

The following tables compare support for different font formats and support for CSS3 font resources for a number of layout engines. Web fonts were initially defined (but later dropped) from CSS2, then added into CSS3. The specification is supported by an increasing number of web browsers.^[1][2]

Explanation of the tables

Engine nomenclature

Rather than the names of web browsers and HTML to PDF converters, the names of the underlying engines are used. Some of the software and online converters that use the various engines are listed below.

Layout engine	Release version	Preview version	Used by
Amaya	11.4.7[3]	N/A	No longer developed; Amaya
Blink	537.36	source code[note 1]	Chromium/Chrome (28+), Opera (15+), Yandex, Liebao and Samsung Browser .
EdgeHTML	13.10586 [4]	N/A	Microsoft Edge, Universal Windows Platform (UWP) JavaScript apps
Gecko	44.0.2 (February 11, 2016[5]) [±] ESR 38.6.1 (February 11, 2016[6]) [±]	Beta 45.0 Beta 6 (February 16, 2016[7][8]) [±] Developer Edition 46.0a2 (January 26, 2016[9]) [±] daily release Nightly 47.0a1 (January 25, 2016[10]) [±] daily release	All Mozilla software, including Firefox; SeaMonkey and Galeon; Camino; K-Meleon; Flock (up to 2.x); Debian IceWeasel; GNU IceCat (formerly GNU IceWeasel); Cyberfox; Icedove, Iceape and Iceowl; Firefox for mobile ("Fennec"). Also used by the Maple platform in 2010 and 2011 Samsung "SmartTV" devices which are based on the build used in Firefox 3.0. Nokia Asha platform is also using Gecko for web apps rendering.
KHTML	4.12.3[11]	N/A	Konqueror[note 2]
Presto	2.12.388	N/A	No longer developed; Opera and Opera Mobile use Blink now; Nintendo DS & DSi Browser; Internet Channel
Prince	10	20160109	HTML to PDF converters: Prince (previously called PrinceXML), DocRaptor. The information in the Prince columns is also true of Prince for Books, a related layout engine.
Tasman	(IE 5.2.3 for Mac)	N/A	No longer developed (aborted in 2003); Internet Explorer 5+ for Mac OS X
Trident	7.0 (IE 11)	N/A	Internet Explorer and other Internet Explorer shells like Maxthon (Microsoft Windows operating systems only), Windows Phone 8
WebKit	534.20	nightly build[note 3]	Tizen (both OS and browser), Safari (both desktop and mobile), Google Chrome (before 28), Maxthon 3, Shiira, iCab 4, OmniWeb 5.5+, Web, Adobe AIR, Midori, Adobe Dreamweaver CS4 and CS5, Android browser, Palm webOS browser, Symbian S60 browser, OWB, Steam, Rekonq, Arora, Flock (version 3+), RockMelt, Dolphin Browser, Sleipnir, Konqueror[note 2]. Used by the LG Smart TV platform to enable web content on TVs. HTML to PDF converters: wkhtmltopdf, PhantomJS, Pdfcrowd[12], http://www.online-convert.com/[13].

1. "chromium / chromium/blink". chromium.googlesource.com. Google. Retrieved 2014-05-27.
2. In Konqueror, the user can switch the used layout engine.
3. "WebKit Nightly Builds". webkit.org. Retrieved 2014-05-27.

Values

Values indicate the level of support in the most recent version of the layout engine, or (if a version number is given) in the specified version. Version numbers without any other value indicate the version at which the layout engine first fully supported the feature.

Value	Meaning
Yes	Indicates that the layout engine fully supports this property/element when valid values are used.
No	Indicates that the property/element is completely ignored.
Partial	Indicates that the property/element is understood, but that not all values are supported. Supported values are implemented correctly.
Incorrect	Indicates that the property/element is understood, but that it is not implemented correctly in all cases.
Experimental	Indicates that the property/element is understood, but supported under an alternate name. May be incomplete or buggy.
Dropped	Indicates that the property/element is no longer supported.
Nightly build	Indicates that the property/element is supported to some extent in an experimental/nightly build. Future support is expected.
Depends	Indicates that the property/element is supported only on certain platforms, or if certain settings are configured.

Support for CSS font resources

CSS3 specified a mechanism for downloading and displaying fonts within a web page.^{[spec 1]} This table compare support for that mechanism. Note that Embedded OpenType (EOT)^{[spec 2]} font download does not bring in the entire OpenType font and therefore, the most prominent feature of Open Type, ligature support, does not come with EOT. Trident before version 5.0 supports only EOT. EOT is not sufficient for smartfonts that rely on ligatures.

		Trident[t 1]	Gecko[g 1]	WebKit[w 1]	Presto[p 1][p 2]
Grammar and rules
CSS3	@font-face	<3.1^[IE 4.0]	1.9.1	525[note 1]	2.2
Descriptors
CSS3	font-family	<3.1^[IE 4.0]	1.9.1	525	2.2
	src	Partial[note 2]
	font-style	<3.1^[IE 4.0]
	font-weight
	font-stretch	5.0[t 3]	9.0[g 2]	No[w 6]	No
	unicode-range		Experimental[g 3]	Partial[note 3]
	font-variant	No	24.0[g 4]	No	No
	font-feature-settings	6.0[t 4]	Experimental[g 5]

Support in HTML and XML documents

This table compares support for font formats applied with the @font-face rule in HTML and XML documents.

Format	Trident	Gecko	WebKit	Presto
Embedded OpenType (EOT)[spec 2]	<3.1^[IE 4.0]	No[g 6]	No[w 8]	No
TrueType (TTF)[spec 3]	5.0[t 3]	1.9.1	525	2.2
OpenType (OTF)[spec 4]
Scalable Vector Graphics (SVG)[spec 5]	No	No[g 7]
Web Open Font Format (WOFF)[spec 6][spec 7]	5.0[t 5]	1.9.2	533[w 9][w 10][w 11]	2.7

Support in SVG documents

This table compares support for font formats applied with the @font-face rule in SVG documents.

Format	Trident	Gecko[g 8]	WebKit	Presto
Embedded OpenType (EOT)[spec 2]	No	No[g 6]	No[w 8]	No
TrueType (TTF)[spec 3]		Yes	Yes	2.2
OpenType (OTF)[spec 4]		18.0	No
Scalable Vector Graphics (SVG)[spec 5]		No[g 7]	525
Web Open Font Format (WOFF)[spec 6][spec 7]		No	No[w 9]	2.7.81

Smart font features support

Format	Trident	Gecko	WebKit	Presto
OpenType liga ligatures[spec 8]	No	2.0	Partial[w 12]	No
OpenType rlig ligatures[spec 9]			No
ZWNJ and ZWJ (Unicode characters used for ligature control)	Yes		Yes	No[p 3]

See also

• Web typography

Notes

1. Prior to version 4.0, Google Chrome had font support disabled.^{[w 2][w 3][w 4][w 5]}
2. Doesn't understand the format() or local() identifiers.^{[t 2]}
3. Doesn't understand multiple, comma-separated ranges.^{[w 7]}

References

Specifications

1. CSS Fonts Module Level 3 - Font resources, W3C
2. Nelson, Paul (2008-03-05), Embedded OpenType (EOT) File Format, Microsoft, Monotype Imaging
3. TrueType Reference Manual, Apple
4. OpenType specification, Microsoft
5. Scalable Vector Graphics (SVG) 1.1 Specification - Fonts, W3C
6. Kew, Jonathan; Leming, Tal; van Blokland, Erik (2010-04-08), WOFF File Format 1.0, W3C, Mozilla, Type Supply, LettError
7. Kew, Jonathan; Leming, Tal; van Blokland, Erik (2009-10-23), WOFF File Format, Mozilla, Type Supply, LettError
8. OpenType Layout tag registry, Tag: 'liga', Microsoft
9. OpenType Layout tag registry, Tag: 'rlig', Microsoft

Trident references

1. About Font Embedding, Microsoft
2. @font-face support in Internet Explorer
3. Internet Explorer Platform Preview Guide for Developers, Microsoft
4. "font-feature-settings property". Microsoft. Retrieved 8 November 2013.
5. Galineau, Sylvain (2010-04-23), Meet WOFF, The Standard Web Font Format, Microsoft

Gecko references

1. @font-face, Mozilla
2. Bug 3512 - (font-stretch) Implement font-stretch property, Mozilla
3. Bug 475891 - implement unicode-range support in user font set, Mozilla
4. Bug 549861 - (font-variant) implement parsing of font feature properties, Mozilla
5. Bug 511339 - implement experimental support for -moz-font-feature-settings, Mozilla
6. Bug 520357 - support new web font format (EOT Lite) in @font-face, Mozilla
7. Bug 119490 - Implement SVG fonts, Mozilla
8. Bug 468237 - SVG image using a font specified via @font-face doesn't use the font after it loads, Mozilla

WebKit references

1. Hyatt, Dave (2007-10-03), Downloadable Fonts, Apple
2. Issue 9633: Disable web fonts by default, Google, 2009-04-01
3. Full pass of acid3 - Chromium-dev, Google, 2009-07-03
4. Issue 17818: Enabled dynamic / web font support in a secure manner, Google, 2009-07-27
5. Irish, Paul (2010-01-25), Chrome and @font-face: It's here!
6. Bug 12530 - CSS3: Support the font-stretch property, WebKit
7. @font-face support in Safari
8. Bug 20542 - Adding EOT Font Rendering capability, WebKit
9. Bug 31302 - Add WOFF support for @font-face, WebKit
10. Bug 38217 - [chromium] Add WOFF support, WebKit
11. Irish, Paul (2010-08-02), Quick Guide to Implement Webfonts via @font-face, HTML5Rocks
12. On Safari, ligatures may be switched on with the CSS setting text-rendering, but then, they are used indiscriminately even when letter-spacing is increased (see Fraktur letterspacing); on Google Chrome, ligatures do not work.

Presto references

1. Mills, Chris (2008-12-04), Opera Presto 2.2 and Opera 10 — a first look, Opera
2. Seven Web Fonts showcases, Opera, 2009-09-01
3. When letter-spacing is increased, these characters are spacing.

Other references

1. Kimler, Scott (2009-07-04), Cross Browser Font Embedding with the CSS3 @font-face selector, Randsco
2. @font-face browser support
3. Amaya Binary Releases, Most recent download link in stable
4. Change log between EdgeHTML 12.10240 and 13.10586
5. "Firefox — Notes (44.0.2) — Mozilla". mozilla.org. 2016-02-11. Retrieved 2016-02-12.
6. "Firefox — Notes (38.6.1) — Mozilla". mozilla.org. 2016-02-11. Retrieved 2016-02-12.
7. "Firefox — Beta Notes (45.0beta) — Mozilla". 2016-01-27. Retrieved 2016-01-29.
8. "Mozilla Firefox Web Browser — Download Firefox Beta in your language — Mozilla". Retrieved 2016-02-17.
9. "Firefox — Aurora Notes (46.0a2) — Mozilla". 2016-01-26. Retrieved 2016-01-29.
10. "RapidRelease/Calendar - MozillaWiki". Retrieved 2016-01-29.
11. Download for kdelibs, Most recent download link in stable
12. Pdfcrowd FAQ, “Pdfcrowd is built around Webkit.”
13. ‘Producer’ metadata in the resulting pdf.