Case Converter

How to convert text case

1. Type or paste your text into the box. It can be a single phrase, a headline or several paragraphs.
2. All nine styles appear immediately below the box and refresh on every keystroke — there is no Convert button to press.
3. Click Copy beside the style you need. Only that one version goes to your clipboard; the text in the box stays untouched, so you can copy a second style straight afterwards.

The case styles explained

• UPPERCASE / lowercase — every letter capital or every letter small. Line breaks and punctuation are kept exactly as typed.
• Title Case — the first letter of every word is capitalised and the rest lowercased.
• Sentence case — everything is lowercased, then the first letter of the text and the first letter after each full stop, question mark or exclamation mark is capitalised.
• camelCase / PascalCase — spaces and punctuation removed; camelCase keeps the first word lowercase, PascalCase capitalises every word.
• snake_case / kebab-case / CONSTANT_CASE — words joined by underscores or hyphens, in lowercase (snake, kebab) or capitals (constant).

A worked example

Typing the quick brown fox produces The Quick Brown Fox (Title Case), theQuickBrownFox (camelCase), TheQuickBrownFox (PascalCase), the_quick_brown_fox (snake_case), the-quick-brown-fox (kebab-case) and THE_QUICK_BROWN_FOX (CONSTANT_CASE). The code styles also work as translators between conventions: paste user_first-name and camelCase returns userFirstName, because underscores, hyphens and spaces are all treated as word boundaries.

Where each style is actually used

• camelCase for variables and functions in JavaScript, Java and Swift; PascalCase for class and component names (React components, C# types).
• snake_case for Python variables, Ruby methods and many database column names; CONSTANT_CASE for environment variables and fixed constants such as MAX_RETRIES.
• kebab-case for CSS class names, URL slugs and file names, since hyphens are safe in addresses and are read by search engines as word separators.
• Sentence case for body text, UI labels and many modern style guides' headings; Title Case for book titles, article headlines and slide titles.

Limits you should know about

Being specific about what this tool does and does not do will save you time on edge cases.

• Title Case is mechanical. It capitalises every word, including small words. war and peace of the east becomes War And Peace Of The East, whereas many style guides (AP, Chicago) keep short articles, conjunctions and prepositions lowercase. Lowercase those by hand after copying if your guide requires it.
• Sentence case lowercases everything first. Proper nouns, acronyms and the pronoun “I” are lowercased too, so I met NASA in Paris comes out as I met nasa in paris. Fix names after converting.
• Code styles only keep English letters and digits. camelCase, PascalCase, snake_case, kebab-case and CONSTANT_CASE treat any other character as a separator and drop it, so an accented letter or non-Latin script disappears: café menu becomes caf_menu. The apostrophe is a separator as well, which turns user's name into userSName.
• Existing camel humps are not split. Text is lowercased before being split into words, so XMLHttpRequest becomes xmlhttprequest in snake_case. Insert spaces before converting if you need xml_http_request.
• Line breaks collapse in the code styles. Multi-line input is joined into a single identifier, so convert one name at a time. UPPERCASE, lowercase and Title Case preserve line breaks.
• Uppercasing follows Unicode rules. The German ß becomes SS in UPPERCASE, which cannot be reversed by lowercasing.

Practical tips

If you received a message typed in ALL CAPS, paste it and copy the Sentence case version, then restore names and acronyms. When preparing a list of CSS class names or file names from plain descriptions, convert each line separately to kebab-case. For URL slugs specifically, the slug generator also strips accents and special characters rather than dropping them, which suits accented titles better.

Is it private and safe?

Yes. The conversion is plain JavaScript running inside your browser tab, on your own device. Your text is never uploaded or stored, which makes it safe for unpublished headlines, internal variable names or confidential drafts.

Related tools: clean up the converted text with the slug generator, remove duplicate lines, sort lines or word counter.