Ultimate Guide to Font Formats
The OpenType font format has taken the lead in modern typography. But there are more font formats available out there, each with their own advantages and disadvantages. Our Ultimate Guide to Font Formats gives you a detailed explanation.
Variable Fonts (VF)
Variable fonts are the new kid on the block, but the concept of a variable font format has been around for a long time, like in the form of the legacy Multiple Master (MM fonts) format. It officially builds on the model established in Apples TrueType GX variations, in the mid-1190s. But with the release of OpenType 1.8 on 14 September 2016, OpenType Font Variations is a fact. ‘The big four’ tech companies Adobe, Apple, Microsoft and Google have agreed on and jointly developed this new format.
For more detailed information, read our article What are OpenType Variable Fonts?
Web Open Font Format (WOFF / WOFF2)
WOFF is the ultimate web font format. It’s basically an OTF or TTF font file with metadata and compression supported by all major browsers. The WOFF font format was created for web fonts. It’s jointly created by the Mozilla Foundation, Microsoft and Opera Software. When fonts are compressed, they load much faster. The metadata structure allows for inclusion of license data within the font file to address copyright issues. It is a World Wide Web Consortium Recommendation and is seen as the future of font formats.
More info about WOFF browser support.
WOFF2 is the evolution of WOFF. It offers a 30% average compression gain over the original WOFF.
More info about WOFF2 browser support.
OpenType Format (OTF)
OpenType is a cross-platform font format created by the combined efforts of Adobe and Microsoft. It has the ability to support widely extended character sets and layout features, which provide extended multilingual- and advanced typographic features. OTF permits storage of up to 65,000 characters. The same font file works on Mac and Windows computers.
OpenType Pro fonts only fully work when you use an application which supports OpenType Features (aka ‘OpenType savvy’), like InDesign, Illustrator or Photoshop. Only with OpenType savvy applications you will provide access to these advanced layout features like ligatures, small caps, different kind of numbers and so on.
Three different levels of support for OpenType fonts can be named.
- Basic Roman support: The application can display texts written using Roman script (English and other Western languages), but there is no support for other languages or advanced typography.
- Multilingual support: The application supports Unicode or its subsets and can display texts written using Roman script as well as other scripts (Cyrillic, Greek, Japanese etc.). In some cases, the multilingual support is limited and there is only partial support for right-to-left scripts or complex scripts such as Arabic, Hebrew or Devanagari.
- Advanced features support: Application supports Unicode and allows the user to access advanced typographic features such as ligatures, small caps or alternates.
There are two types of so-called OpenType flavors:
- .OTF: Created with PostScript metrics
- .TTF: Created with TrueType metrics
The OpenType format is an extension of the TrueType SFNT format that also can support Adobe PostScript font data and new typographic features.
OpenType TTF fonts are internally practically the same format as Windows TrueType fonts, so there are no problems getting such fonts to work in Windows. They will even be displayed on Windows 3.1.
For more information about the OpenType font format, please visit Adobe’s introduction to OpenType.
More info about OTF browser support.
TrueType Format (TTF)
TrueType fonts are the basic for the OpenType font format. It’s an outline font standard originally developed by Apple Computer in the late 1980s as a competitor to PostScript Type 1 fonts. TrueType fast became the most common format for fonts on both the Mac OS and Microsoft Windows operating systems.
The primary strength of TrueType was originally that it offered font developers a high degree of control over precisely how their fonts are displayed, right down to particular pixels, at various font sizes. With widely varying rendering technologies in use today, pixel-level control is no longer certain in a TrueType font.
More info about TTF browser support.
Scalable Vector Graphics (SVG)
SVG fonts support was developed to provide a common font format for SVG that is guaranteed to be supported by all conforming SVG viewers, SVG provides a facility to define fonts in SVG. This facility is called SVG fonts (source). Fonts in SVG files are implemented with the @font-face element.
There are also SVG fonts who are defined using the SVG ‘font’ element. Their purpose is to allow for delivery of glyph outlines in display-only environments.
SVG fonts do not provide font hinting, making them possibly look less good on screen. SVG support across browsers is still not consistent. If you’re targeting iPhone and iPad users, SVG fonts are your only chance. Only SVG font are allowed by version 4.1 and below of Safari for iOS.
Embedded OpenType (EOT)
EOT fonts are designed by Microsoft to be used as embedded fonts on the web. It is their solution to tackle the copyright issues of TTF and OTF fonts, when published online. EOT fonts are only supported by Microsoft Internet Explorer!
Compression and subsetting make the font files smaller. Subsetting provides some copyright protection, but EOT also uses encryption for further protection.
More info about EOT browser support.
PostScript (PS)
The PostScript page description language, and PostScript fonts, were developed by Adobe Systems.
PostScript Type 1 and Type 3 fonts were introduced by Adobe in 1984 as part of the PostScript page description language. It hit the market on a large scale in March 1985, when the first laser printer to use the PostScript language, the Apple LaserWriter, was introduced.
PostScript Type 1 is considered a legacy font format. It’s not cross-platform compatible and Unicode is not supported.
Clear font caches
If you run into problems with fonts due to the different font formats on your PC, the first thing you wanna do is to clear font caches. Read our Support article on clearing font caches on your PC.