Case Converter
Switch any text between ten letter cases — from plain sentence case to the camelCase and snake_case conventions used in code — in a single click.
Choose a conversion
About the Case Converter
Retyping a paragraph because it arrived in capitals is one of the small, avoidable time sinks of working with text. It happens constantly: a product feed exports every title in ALL CAPS, a colleague sends notes with caps lock stuck on, a CSV column comes back in inconsistent casing, or a heading style needs converting from title case to sentence case because the house style guide changed.
This converter handles ten cases in total. The four everyday ones — UPPERCASE, lowercase, Title Case and Sentence case — cover editorial work. The programming conventions — camelCase, PascalCase, snake_case, kebab-case and CONSTANT_CASE — cover variable names, database columns, CSS classes, file names and URL slugs. Alternating case and inverse case round it out for the times you need them.
Title case here follows the convention most style guides share: principal words are capitalised, while short articles, conjunctions and prepositions such as a, an, the, and, of, in and to stay lowercase unless they open or close the title. Sentence case capitalises the first letter after each terminal punctuation mark and leaves the rest alone, so acronyms you typed in capitals are not flattened.
How to use it
- Paste your textDrop in a word, a headline, a paragraph or a whole column of exported data. Line breaks are preserved through every conversion.
- Pick a caseChoose from the ten conversion buttons. The result replaces the text in the editor so you can chain conversions if you need to.
- Check the previewBecause the conversion happens in place you can immediately see whether title case handled your acronyms and short words the way you wanted.
- Undo if neededThe undo button restores the previous version, so experimenting with different cases costs nothing.
- Copy or downloadCopy the converted text in one click, or save it as a .txt file if you are working with a long list.
Features
- Ten conversionsUPPERCASE, lowercase, Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE and aLtErNaTiNg.
- Smart title caseShort articles, conjunctions and prepositions stay lowercase mid-title, exactly as major style guides prescribe.
- Acronym awareSentence case only changes the first letter of each sentence, so NASA and HTML survive the conversion intact.
- Line breaks preservedConvert a whole list at once — every line keeps its position, which matters for data columns.
- Undo historyStep back through conversions if a transformation was not what you wanted.
- Instant and offlineConversion is local JavaScript, so it is immediate and works with no network connection.
Who uses this tool
- Editors and copywritersNormalise headlines to house style, or convert a screaming all-caps submission into readable sentence case in one click.
- DevelopersRename a phrase into a valid variable, CSS class, database column or file name without hand-editing each separator.
- Data cleanersStandardise a column of names, cities or product titles that arrived from three different systems with three different conventions.
- StudentsFix a document where caps lock was on for a paragraph, without retyping any of it.
Tips worth knowing
- Convert to lowercase first when text arrives in ALL CAPS, then apply title or sentence case — going straight from capitals loses the original word boundaries the converter uses.
- kebab-case output is exactly what you want for URL slugs and CSS class names; snake_case is the convention for Python variables and most SQL column names.
- Title case rules differ between AP, Chicago and MLA. This tool follows the common short-word convention, so check a specific style guide if you are writing for publication.
Frequently asked questions
What is the difference between title case and sentence case?
Title case capitalises the principal words in a heading — “The Complete Guide to Online Tools”. Sentence case capitalises only the first word and any proper nouns — “The complete guide to online tools”. Most modern digital style guides prefer sentence case for headings because it reads faster and is friendlier to screen readers.
Will the converter break my acronyms?
Sentence case and title case leave existing capitalisation inside words alone, so NASA, HTML and PDF survive. Lowercase and camelCase conversions will flatten them by design, since that is the point of those conversions.
What is camelCase versus PascalCase?
Both remove the spaces and capitalise each subsequent word. camelCase leaves the first letter lowercase (userFirstName) and is the convention for JavaScript variables and functions. PascalCase capitalises it too (UserFirstName) and is used for class names in most languages and for React components.
Can I convert a whole list at once?
Yes. Paste as many lines as you like — every line is converted independently and line breaks are preserved, so a column pasted from a spreadsheet comes back in the same order and can be pasted straight back.
Does converting case change any other characters?
No. Punctuation, digits, emoji and accented characters pass through untouched. Accented letters are converted correctly — é becomes É in uppercase — because the tool uses your browser's Unicode-aware case mapping.
Is there a character limit?
No. The converter handles anything from a single word to a document of several hundred thousand characters without a server round trip, so long lists convert as fast as short ones.