How to use the Case Converter
- 1Type or paste your text into the box.
- 2Click a button to convert it: UPPERCASE, lowercase, Title Case, Sentence case, camelCase, snake_case or kebab-case.
- 3Click Copy to copy the converted text to your clipboard.
- 4Click Clear to empty the box and start again.
Text cases for writing
UPPERCASE turns every letter into a capital. It is used for acronyms, short labels and warnings, but long passages in capitals are harder to read and can come across as shouting. lowercase does the opposite and is handy for cleaning up text that was typed with Caps Lock on.
Title Case capitalises the first letter of each word and is common in headlines, book titles and headings. Formal style guides such as AP and Chicago keep short words like a, and, of and the in lowercase unless they start the title, so check the result against the guide you follow. Sentence case capitalises only the first letter of each sentence, which is how normal prose is written and is increasingly popular for headings and interface text because it reads naturally.
Naming conventions in programming
Code identifiers cannot contain spaces, so programmers join words using a consistent convention. camelCase starts with a lowercase letter and capitalises each following word, as in userFirstName. It is the standard for variables and functions in JavaScript, Java and many other languages. If you are renaming keys in JSON data, the JSON formatter can tidy and validate the result.
snake_case writes words in lowercase separated by underscores, as in user_first_name. It is the recommended style for variables and functions in Python and Ruby and is widely used for database column names. kebab-case uses hyphens instead, as in user-first-name, and is common in URLs, CSS class names, HTML attributes and file names. Using hyphens in URLs also helps search engines read the separate words. For web addresses, the URL slug generator turns a title into a clean, URL-ready slug.
Why use a case converter?
Retyping text to fix capitalisation is slow and error-prone. A converter lets you reformat a heading list, fix a paragraph typed in capitals, or turn a plain-English phrase into a variable name or URL slug in seconds. When converting to camelCase, snake_case or kebab-case, punctuation is dropped and words are joined using the chosen separator. If your list also contains repeated entries, you can clean it up with the remove duplicate lines tool.
The conversion happens in your browser, so you can safely paste confidential documents or code. Nothing is uploaded or stored. To check the length of a heading or paragraph after converting it, use the word counter.
Learn more
Frequently asked questions
What is the difference between Title Case and Sentence case?
Title Case capitalises the first letter of most or all words, as in The Quick Brown Fox. Sentence case capitalises only the first word of each sentence and proper nouns, as in The quick brown fox. Sentence case is how ordinary prose is written.
Will Sentence case keep capitals on names and places?
No. An automatic converter cannot tell which words are proper nouns, so names, places and acronyms will be lowercased except at the start of a sentence. Review the result and recapitalise those words where needed.
What is camelCase used for?
camelCase is a naming style for code where words are joined without spaces and each word after the first starts with a capital letter. It is the usual convention for variable and function names in JavaScript, TypeScript and Java.
Should I use snake_case or kebab-case?
Follow the convention of the place where the name will be used. snake_case is standard in Python code and many databases, while kebab-case is preferred for URLs, CSS classes and file names. Many languages do not allow hyphens in variable names, so kebab-case is rarely used for identifiers.
Is there a limit on how much text I can convert?
There is no fixed limit. Because everything runs locally in your browser, very large texts are limited only by your device’s memory and speed. More writing utilities are in the text tools section.