Case & naming
Sentence case converter
Paste messy caps and get readable sentences — first letter up, the rest down, with I and proper nouns handled on your device.
Processed in your browser — nothing is uploaded
A sentence case converter is the default voice of email, documentation, and UI copy. This tool walks your paste, lowercases the body, lifts the first letter of each sentence, and restores the pronoun I. Keep smart casing enabled if you want brands and acronyms to survive the pass.
Use it when someone sent you a block of caps, when a heading needs to become a paragraph, or when you want a calmer tone than Title Case. Pair it with the Title Case converter when you are switching between headlines and body copy. To drop every letter, including the first, use the lower case converter.
Last reviewed 2026-09-10.
FAQ
Questions, answered
What is sentence case?
Sentence case capitalizes the first letter of each sentence and leaves the remaining letters lowercase, the same pattern you use in everyday prose.
Does it capitalize names?
Yes, when smart casing is on. Built-in terms such as NASA, iPhone, and JavaScript are restored after the sentence-case pass. You can turn that off if you want a strict lowercase body.
How are sentences detected?
A new sentence starts after a period, question mark, exclamation point, or ellipsis followed by a space, and at the start of a line.
Does my text leave the browser?
No. Conversion runs in JavaScript on this page. There is no account and no server-side processing.
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Title Case
Title case converter with AP, APA, Chicago, and MLA small-word rules. Also an AP title case converter for headlines.
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Capitalized Case
Capital case converter and proper case converter: capitalize the first letter of every word (Start Case).
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lower case
Convert uppercase to lowercase online. Capital to small letters converter — Word and Excel alternatives, in your browser.