What is Sentence Case?
Sentence case is the standard capitalization format used in written English prose, essays, journalism, and academic articles. In sentence case, only the first letter of the first word in a sentence is capitalized, along with any proper nouns (such as names of people, places, brands, and organizations). All other words are formatted in lowercase.
Input: THIS IS AN EXAMPLE. WE ARE TESTING SENTENCE CASE.
Result: This is an example. We are testing sentence case.
Rules for Capitalizing in Sentence Case
- Sentence Openers: The first letter immediately following a period (.), exclamation point (!), or question mark (?) is automatically capitalized.
- Paragraph Boundaries: The first character after a new line or paragraph break is capitalized.
- Proper Noun Preservation: Brand names like iPhone, YouTube, and ChatGPT retain their canonical casing via our built-in proper noun dictionary.
When to Use Sentence Case vs. Title Case
In modern digital product design and UI/UX writing (including guidelines from Apple, Google Material Design, and Microsoft Fluent), sentence case is the recommended standard for buttons, navigation items, dialog titles, and notifications because it is faster to read and feels more conversational. Title case is reserved for major publication headlines and formal book titles.