Title case, snake_case, or a URL slug: which casing?

Pick the right casing tool for prose headings, code identifiers, URLs, and accidental all-caps text.

Casing is a destination decision: a headline follows editorial rules, a variable follows a language convention, and a URL follows address rules. Applying the wrong converter produces text that looks deliberate but fails where it is used.

Use prose casing for anything a person reads

The case converter switches between uppercase, lowercase, title and sentence case. Title case is for headings, sentence case for body copy, and neither is safe for identifiers because spaces and capitals carry no meaning there.

Use code casing for identifiers

The code case converter produces camel, Pascal, snake, kebab, constant, dot and path forms from ordinary words. Choose by the language and context: snake_case for Python variables, camelCase for JavaScript, constant case for environment keys.

Use a slug for addresses, not for display

The slug generator lowercases words, removes punctuation and joins them with hyphens, with an ASCII-safe option. Use it for URLs and file names; keep the original title for the visible heading so the page still reads naturally.

Tools covered in this guide

Case Converter
Switch text between uppercase, lowercase, title, and sentence case.
Code Case Converter
Convert words to camel, Pascal, snake, kebab, constant, dot or path case.
Slug Generator
Turn any title into a clean URL slug, in Unicode or ASCII-safe form.
Swap Text Case
Invert the case of every letter: uppercase becomes lowercase and vice versa.

Frequently asked questions about text casing

Does title case capitalise small words like of and the?

Editorial title case usually lowercases short articles and prepositions unless they open or close the title. Check the output rather than assuming every word is capitalised.

Which casing should a URL use?

Lowercase with hyphens is the safest default, because paths are case-sensitive on many servers and underscores are harder to read aloud.

What is swap case for?

It inverts every letter, which is useful for correcting text typed with caps lock on or for producing a stylistic effect, not for normal casing work.