Sentence Case Converter
Convert any text to sentence case, capitalizing the first letter of each sentence.
This tool runs entirely in your browser. Your files are never uploaded to a server.
Paste your text to lowercase everything and automatically capitalize the first letter of the text and the first letter after every period, question mark, or exclamation point — just like natural sentence writing.
Frequently Asked Questions
- How does it handle abbreviations like "Mr." or "U.S."?
- Since capitalization is triggered by any period, the tool can't tell an abbreviation's period from a sentence ending, so a letter right after "Mr." may get capitalized unintentionally — worth a quick check on text with abbreviations.
- What happens if my text already has mixed capitalization?
- It's overridden — the tool first lowercases the entire input, then capitalizes only the first letter of the text and the first letter after each sentence-ending punctuation mark.
- Can I switch to a different case style afterward?
- Yes — this tool includes a mode switcher, so you can instantly try uppercase, lowercase, title case, capitalized case, alternating case, or inverse case on the same text.