Sentence Case Converter
Convert text to sentence case, capitalizing the first letter of each sentence.
Converted live as you type. 0 words, 0 characters. Nothing leaves your browser.
Options
How to convert text to sentence case
Paste your text
Type or paste the text you want to fix into the input box.
Set the option
Optionally capitalize the first letter after a colon as well as after full stops.
Copy the result
The sentence-cased text updates live. Copy it with one click.
Why use this tool
Real sentence detection
Capitalization is applied after full stops, question marks, exclamation marks, and line breaks, not just the first word.
Fixes the pronoun I
The standalone word I and its contractions like I am and I will are capitalized wherever they appear.
Live word and character count
A running count of words and characters sits under the input so you can see the size of your text.
Optional colon handling
A toggle decides whether the first letter after a colon is capitalized, which suits titles and labels.
Private by design
All conversion runs on your device. Nothing you type leaves the page. No upload, no signup.
About this tool
Sentence case means only the first letter of each sentence is capitalized, along with proper nouns, exactly how ordinary prose is written. Text that arrives in ALL CAPS, in Title Case, or with random capitalization is hard to read and looks unpolished. This converter lowercases everything first, then raises the first letter of each sentence back up.
Sentences are detected after full stops, question marks, exclamation marks, and line breaks, so multi-line and multi-sentence text is handled in one pass. The standalone pronoun I is always capitalized, including contractions such as I am and I will, which is the most common thing plain lowercasing gets wrong. An optional setting also capitalizes the first letter after a colon.
Everything updates live as you type, with a running word and character count under the input. Because it lowercases before recapitalizing, it cannot always know that an abbreviation like e.g. is not the end of a sentence, so give the result a quick read for edge cases. For other transformations try the title case converter or the general case converter.
Frequently asked questions
- What is sentence case?
- Sentence case capitalizes only the first letter of each sentence plus proper nouns, leaving the rest lowercase. It is how normal paragraphs and prose are written.
- Does it capitalize the word I?
- Yes. The standalone pronoun I is always capitalized, including contractions like I am, I have, and I will.
- How are sentences detected?
- A new sentence is assumed after a full stop, question mark, exclamation mark, or line break. You can also opt in to capitalize after colons.
- Will it handle abbreviations correctly?
- Mostly, but because it lowercases first, an abbreviation such as e.g. that is followed by more text may trigger a capital. Give the output a quick check for those cases.
- Is my data sent anywhere?
- No. Everything runs in your browser as you type. Nothing is uploaded and no account is needed.
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