Sentence case formatter
Convert text to sentence case online. Capitalize the first letter of each sentence and lowercase the rest, with options to keep acronyms and mixed-case words.
How to use
Use this tool to normalize capitalization without changing your spacing or punctuation.
- Paste or type your text in the input box.
- Choose options (acronyms, mixed-case words, new lines).
- Click Format to sentence case.
- Copy the output.
FAQ
What does “sentence case” mean?
It capitalizes the first letter of each sentence and lowercases the rest of the sentence.
Does it keep my spacing and punctuation?
Yes. It keeps your original whitespace and punctuation; it mainly changes letter casing.
Will it capitalize after . ! and ?
Yes. The tool starts a new sentence after those punctuation marks.
Can new lines start a new sentence?
Yes. Enable “Treat new lines as sentence breaks” to capitalize after each line break.
How can I prevent acronyms like NASA from becoming “Nasa”?
Turn on “Keep ALL CAPS words” to preserve words that are already fully uppercase.
Will it keep brand-style casing like iPhone or eBay?
Yes, if “Keep mixed-case words” is enabled, words that already contain both upper and lower case are left unchanged.
Is my text uploaded to a server?
No. Formatting runs locally in your browser and the tool does not make network requests.
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