Text Case Converter

Switching between camelCase, snake_case, and friends

A case converter rewrites a phrase into a naming convention without you retyping it. The common targets are camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, and Title Case. Each ecosystem has a preferred style: JavaScript variables lean camelCase, Python uses snake_case, CSS classes and URL slugs use kebab-case, and environment variables shout in CONSTANT_CASE.

Why it is harder than it looks

The tricky part is detecting word boundaries in the input. The tool has to split on spaces, hyphens, underscores, and the hidden boundaries inside camelCase itself. Acronyms are the classic edge case: should parseJSON become parse_json or parse_j_s_o_n? Good converters treat runs of capitals as a single token.

Example

Input phrase:

user profile image URL

Converted outputs:

camelCase:    userProfileImageUrl
PascalCase:   UserProfileImageUrl
snake_case:   user_profile_image_url
kebab-case:   user-profile-image-url
CONSTANT:     USER_PROFILE_IMAGE_URL

FAQ

What happens to numbers? Digits usually stay attached to the preceding word, so address line 2 becomes addressLine2, not addressLine_2.

Can I round-trip safely? Not always. Converting to snake_case and back to camelCase works, but information about original capitalization of acronyms can be lost along the way.

Which case for a URL? Use kebab-case. For a title to URL, pair this with the slug generator instead, since it also strips accents and punctuation.