The Sentence Case Converter reformats any text so the first letter of each sentence is capitalized and the rest is lowercase. It's the quickest way to fix ALL CAPS emails, clean up dictated text, or normalize inconsistent capitalization from AI outputs or scraped content.
What is sentence case?
Sentence case is the default capitalization style for prose in English. Only the first letter of each sentence — and proper nouns — is capitalized; everything else is lowercase. It's what you use in body paragraphs, chat messages, and casual writing.
How to use the Sentence Case Converter
- 1Paste your text into the input on the left.
- 2The tool converts it to sentence case instantly on the right.
- 3Copy the cleaned-up result and paste it wherever you need it.
Sentence case examples
| Input | Output |
|---|---|
| HELLO WORLD. THIS IS A TEST. | Hello world. This is a test. |
| the quick brown fox. jumps over. | The quick brown fox. Jumps over. |
| why is this in caps? IT IS ANNOYING. | Why is this in caps? It is annoying. |
Popular uses
- Fixing emails typed in ALL CAPS.
- Cleaning up AI-generated content that comes back inconsistently capitalized.
- Reformatting subtitle or transcript text.
- Normalizing user-submitted form input.
- Rewriting SHOUTY social media posts before reposting.
- Preparing chat logs, support tickets, and OCR output for readable publishing.
Why use CaseConvert's Sentence Case Converter?
- Free forever — no signup, no trials, no hidden fees.
- Private by design — everything runs locally in your browser, so your content never leaves your device.
- Works offline once loaded — great for travel or spotty connections.
- No install — works in Chrome, Safari, Firefox, Edge, and every modern mobile browser.
- Fast — output appears instantly as you type or upload.
- Unlimited use — no character caps, no daily quotas, no watermarks on the output.
Frequently asked questions
The converter lowercases everything except the first letter of each sentence. Proper nouns (like iPhone or New York) will need manual capitalization afterwards — see our Title Case tool if you need name-friendly capitalization.
It splits on . ! ? followed by whitespace. Abbreviations like "Dr." may occasionally cause a false split — review the output for edge cases.
Yes — free, no signup, no limit.
No, everything runs in your browser.
Sentence case capitalizes only the first letter of each sentence. Title case capitalizes the first letter of most words, keeping articles (a, an, the) lowercase.
Yes, in any modern browser.
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Keep your text workflow moving with these related converters from CaseConvert. Every tool is free, works offline in your browser, and pairs well with the Sentence Case Converter.