Firefox OS typography

Typeface

An open font with 897 characters (and therefore enormous localization potential), Open Sans is our default typeface for websites, print and other materials.

The Open Sans type family is used in the four weights shown here for all our communications. Open Sans Extrabold Italic in all caps is used as our display type to capture our bold voice and the spirit of the Firefox OS brand (with approved headlines only).

Open Sans Extrabold and Italic

Aa Aa 123 123

Open Sans Bold and Italic

Aa Aa 123 123

Open Sans Regular and Italic

Aa Aa 123 123

Open Sans Light and Italic

Aa Aa 123 123

Typography basics

  • Headlines (approved only)
  • All caps
  • Open Sans Extrabold Italic
  • Size: 80pt
  • Line spacing: 90% of font size
  • Tracking: -25

BLAZE YOUR OWN PATH

  • Headlines (all others)
  • Open Sans Light
  • Size: 80pt
  • Line spacing: 90% of font size
  • Tracking: -25

Make every moment count

  • Subheads
  • Open Sans Bold
  • Size: 20pt
  • Line spacing: 120% of font size
  • Tracking: default

Firefox OS adapts to your life so you can live every moment to its fullest.

  • Body copy
  • Open Sans Regular
  • Size: 15pt
  • Line spacing: 120% of font size
  • Tracking: default

Vestibulum ante ipsum primis in faucibus orci luctus et ultrices posuere cubilia Curae; Vivamus malesuada libero sit amet ligula Nulla facilisi. Sed tincidunt porta magna varius tempus. Nulla lobortis magna a nulla feugiat non tincidunt odio dictum.

International typography basics

Diacritics
To accommodate diacritical marks in international languages, headlines should use one of two choices of line spacing.

Headlines with diacritics above letters should set line spacing at 100%. Headlines with diacritics both above and below letters should set line spacing at 120%.

Always follow common design sense when adjusting the leading on headlines. Diacritical marks should never interfere with one another.

  • Headlines with diacritics above
  • Open Sans Extrabold Italic
  • Size: 80pt
  • Line spacing: 100% of font size
  • Tracking: -25
Headlines with diacritics above
  • Headlines with diacritics above and below
  • Open Sans Extrabold Italic
  • Size: 80pt
  • Line spacing: 120% of font size
  • Tracking: -25
Headlines with diacritics above and below

Typography don’ts

Upper and lowercase text example

Don't use upper and lowercase text for extrabold italic headlines

Disproportionate example

Don’t condense or scale the type disproportionately

Off-brand headlines example

Don't use the Extrabold capitalized italics treament for off-brand headlines.

Wrong font example

Don’t use the wrong font

Extrude example

Don’t extrude the type

Excessive tracking or leading example

Don’t use excessive tracking or leading

Longer than 4 lines example

Don’t make headlines longer than 4 lines

Blur and drop shadow example

Don’t blur or add a drop shadow to the text