Capitalization

Types

Sentence case: Capitalize the first word of the text element, as well as any proper nouns.

Title case: Capitalize every word in the text, except:

  • Articles (a, an, the), unless they appear as the first word in a sentence
  • Coordinating conjunctions (and, or)
  • Prepositions (for, by, from), except the first or last word in a sentence
  • Infinitives (to, in, an)

To check if you're using title case correctly, put your text into Capitalize My Title using the AP setting.

 

Guidelines

For desktop browsers, Android browsers, and websites:

Default to sentence case to support scanning and strike a friendlier, more human tone. We sentence case the following:

  • Headlines
  • Buttons

While sentence case is the default, there are a few exceptions:

Label

Casing

Acronyms

All caps (URL, etc.)

Android snackbars

All caps (UNDO, DELETE)

Brands and products

Title case proprietary names (Mozilla, Firefox, etc.)

Context menus within operating systems

Title case

Feature names

Casing will depend on the feature. (See the word list). We don’t capitalize features such as “new tab,” “shortcuts,” or “passwords,” because they’re not proprietary.

Global Operating System menu bar

Title case

Tab audio state

All caps (PLAYING, MUTE TAB, MUTED)

 

For the Firefox iOS browser:

Follow Apple's Human Interface Guidelines, which use headline-style capitalization. Capitalize every word except articles, coordinating conjunctions, and prepositions of four or fewer letters. Sentence case can be used for headlines written as a complete sentence with ending punctuation.

The following elements should always use title case: