Case Converter

Convert text between UPPERCASE, lowercase, Title Case, Sentence case, camelCase, snake_case and more.

🔒 100% private — files are processed on your device and never uploaded to any server.

Nine capitalisation styles, one paste

The caps-lock paragraph that needs civilising, the lowercase email that needs sentence capitals, the headline that needs Title Case, the column of labels that must become snake_case database fields — letter case is trivial to describe and tedious to fix by hand. This converter takes your text once and offers nine transformations at a button each, from the everyday (UPPER, lower, Sentence) to the programmer set (camelCase, PascalCase, snake_case, kebab-case) to the ironic (aLtErNaTiNg).

How to convert case

  1. Paste or type your text in the top box.
  2. Click any style button — the result appears in the bottom box immediately.
  3. Try as many styles as you like (each works from the original input), then Copy result.

The everyday four

UPPERCASE for headings, labels and warnings — and for nothing longer, since all-caps prose reads as shouting and measurably slows reading. lowercase rescues accidental caps-lock and feeds systems that demand lowercase input. Sentence case capitalises the first letter after each sentence boundary — the fastest repair for transcripts and hurried notes. Title Case capitalises each word for headlines and document titles; this implementation capitalises every word including short ones, the simple convention that never embarrasses (editorial styles that lowercase “of/and/the” vary by style guide anyway).

The programmer set

Multi-word names must become single tokens in code, and each ecosystem has its dialect: camelCase (userFirstName) for JavaScript/Java variables, PascalCase (UserFirstName) for class names, snake_case (user_first_name) for Python and SQL columns, kebab-case (user-first-name) for CSS classes, file names and URLs. The converter handles word-splitting (spaces and punctuation both split), so “User First-Name” converts cleanly into any of the four. Renaming a batch of fields between conventions — pasting a column list and converting — is this tool's quiet superpower.

Worth knowing

  • Numbers and symbols pass through unchanged; only letters change case.
  • Unicode-aware: accented and non-Latin letters upper/lowercase correctly where the language defines it.
  • Acronyms: Sentence case will lowercase NASA mid-sentence — proofread when the text contains them.
  • aLtErNaTiNg exists because the internet demanded it; use ironically.

One paste, nine outputs, zero retyping — and like every tool on this site, your text never leaves the browser.

Quick reference

PropertyDetail
Everyday stylesUPPERCASE, lowercase, Title Case, Sentence case
Code stylescamelCase, PascalCase, snake_case, kebab-case
BonusaLtErNaTiNg sPoNgEcAsE
Word splittingSpaces and punctuation both split words
UnicodeAccented/non-Latin letters handled correctly
WorkflowAll styles work from the original input
Processing100% in-browser, no upload

Frequently asked questions

Which case should I use for headlines?

English convention: Title Case for headlines and document titles, Sentence case for web headings and UI text (the modern trend). Pick one per project and stay consistent — consistency reads more professional than either choice.

What's the difference between camelCase and PascalCase?

Only the first letter: camelCase starts lowercase (userName — variables and functions), PascalCase starts uppercase (UserName — classes and types). Most style guides assign them exactly those jobs.

Why did Sentence case lowercase my acronym?

The converter can't know NASA from Nasa without a dictionary — it applies the rule mechanically. After converting, skim for acronyms and proper names; they're the two things needing a manual touch.

Does conversion change anything besides letters?

No — numbers, punctuation, spacing and line breaks pass through untouched (except in the code styles, where separators become the convention's connector). What you paste is structurally what you get back.