Free Online Text Case Converter
This free online case converter changes the capitalization of any text instantly: convert to UPPERCASE, lowercase, Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, and more. It is equally useful for writers fixing a headline typed with Caps Lock on and for developers renaming identifiers between naming conventions.
Everything runs locally in your browser using JavaScript — the text you paste is never uploaded, stored, or transmitted, so it is safe to use with private notes, code, or unpublished copy.
How to use Text Case Converter
- Paste or type your text into the Input box.
- Select the target case style, for example Title Case or snake_case.
- Press Process to convert the text.
- Copy the result to your clipboard or download it as a .txt file.
Supported case styles
- UPPERCASE — every letter capitalized, e.g. "HELLO WORLD". Common for headings, acronyms, and emphasis.
- lowercase — every letter in small letters, e.g. "hello world". Useful for normalizing shouty text.
- Title Case — the first letter of each word capitalized, e.g. "Hello World". Common for headlines and book titles.
- Sentence case — the first letter of each sentence capitalized, e.g. "Hello world. How are you?".
- camelCase — words joined without spaces, first word lowercase, e.g. "helloWorld". The convention for variables in JavaScript and Java.
- PascalCase — like camelCase but with the first word capitalized too, e.g. "HelloWorld". Used for class and component names.
- snake_case — words joined with underscores, e.g. "hello_world". The convention in Python and SQL.
- kebab-case — words joined with hyphens, e.g. "hello-world". Used in URLs and CSS class names.
- CONSTANT_CASE — uppercase with underscores, e.g. "HELLO_WORLD". Used for constants and environment variables.
- aLtErNaTiNg cAsE and InVeRsE CaSe — novelty styles that alternate or flip the capitalization of each letter.
Related terminology
- Capitalization
- The use of uppercase versus lowercase letters in text, governed by style rules that differ between languages, brands, and programming conventions.
- Naming convention
- An agreed pattern for writing identifiers in code, such as camelCase for JavaScript variables or snake_case for Python functions.
- String transformation
- Any operation that rewrites text according to a rule — case conversion is one of the most common string transformations in programming.
Frequently asked questions
- How do I convert uppercase text to lowercase online?
- Paste the text into the input box, select "lowercase", and press Process. The converted text appears immediately and can be copied with one click.
- What is the difference between Title Case and Sentence case?
- Title Case capitalizes the first letter of every word ("The Quick Brown Fox"), while Sentence case only capitalizes the first letter of each sentence ("The quick brown fox").
- What is the difference between camelCase, PascalCase, and snake_case?
- All three join words together for use in code. camelCase starts lowercase (myVariableName), PascalCase starts every word uppercase (MyClassName), and snake_case separates words with underscores (my_variable_name).
- Is my text uploaded to a server?
- No. The conversion happens entirely in your browser with JavaScript, so your text never leaves your device.