Text Case Converter

Convert text between upper case, lower case, title case, sentence case, camelCase, snake_case and kebab-case. Useful for cleaning up pasted content, normalising headings, and formatting identifiers for code.

Which case to use where

Sentence case capitalises only the first word and proper nouns. It is the standard for body text and, increasingly, for headings — it reads more naturally and is the default in most modern style guides. Title Case capitalises major words. Conventions differ between style guides on which small words stay lower case, so consistency within a document matters more than picking the "correct" variant. UPPER CASE is worth using sparingly. Blocks of capitals are measurably slower to read because the uniform letter height removes the word-shape cues readers rely on, and in messages it is widely read as shouting.

Programming conventions

The identifier cases are not interchangeable, and each ecosystem has settled conventions. camelCase is standard for variables in JavaScript and Java. snake_case dominates Python and SQL column names. kebab-case is used for URLs, CSS class names and HTML attributes, since those contexts treat underscores and capitals inconsistently. URLs in particular should use hyphens rather than underscores — search engines have long treated hyphens as word separators and underscores as joiners.

When conversion needs a human check

Automatic case conversion cannot know your intent. Acronyms are the clearest example: converting "NASA launched a probe" to title case is fine, but converting text that is entirely upper case back to sentence case will turn "NASA" into "Nasa". Proper nouns have the same problem in reverse. Always read the result rather than trusting it, particularly for names, brands and technical terms with unusual capitalisation.

Quick tips

• Converting from ALL CAPS loses acronym and proper-noun information — check names afterwards.
• Use kebab-case for URLs; hyphens are treated as word separators by search engines.
• Sentence case for headings is now the more common house style than Title Case.
• Conversion happens as you type and nothing leaves your browser.

What is camelCase vs kebab-case?

camelCase starts lowercase and capitalizes subsequent words (e.g. myVariableName). kebab-case separates words with hyphens (e.g. my-variable-name).