In text, follow the standard capitalization rules for American English. Additionally:

  • Don't use all-uppercase for emphasis.
  • Follow the official capitalization for the names of brands, companies, software, products, services, and the like.
  • Avoid camel case and all caps. Some screen readers read capitalized letters individually, and some languages are unicase.

Capitalization in titles and headings

In document titles and page headings, use sentence case. That is, capitalize only the first word.


  • For proper nouns, trademarks, keywords, and other terms that are always capitalized a certain way, use the standard capitalization for the term, regardless of where it appears in the title or heading.
  • If you use a colon in a heading, treat what follows the colon as a separate heading, with an initial capital letter of its own.

Even though you're using sentence case, don't put a period at the end of a heading.

Capitalization and colons

Use a lowercase letter to begin the first word of the text immediately following a colon, unless the text is one of the following:

  • A proper noun (Open source software: Istio).
  • A quotation (Arthurian wit: "Bring me yon sworde").
  • An item in a bulleted, numbered, or definition list—for example:
    • Descriptive analytics: Analyzing real-time and historical data to understand past behaviors.
  • Text that follows a label, such as Caution or Note.
  • A subheading on the same line as a heading (Migrating to GCP: Best practices).

Capitalization and figures

Use sentence case for captions and other figure-related text.

Capitalization in glossaries and indexes

Use lowercase for glossary and index terms unless the term is a proper noun or has another reason to require capitalization.

Use sentence case for glossary definitions.

Capitalization and hyphenated words

When a hyphenated word is the first word in a sentence or in a heading, capitalize only the first element in the word, unless a subsequent element is a proper noun or proper adjective.

Capitalization in lists

Use sentence case for items in all types of lists.

Capitalization for tables in text

Use sentence case for all the elements in a table: contents, headings, labels, and captions.

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Google Developer Documentation Style Guide
Google Developer Documentation Style Guide