How do I convert camelCase to snake_case?

Paste the camelCase text, choose snake_case as the target, and the Case Converter inserts underscores at each word boundary, for example helloWorld becomes hello_world.

Can I convert a whole list of items at once?

Yes. Each line is converted independently, so you can paste a column of names or identifiers and they all convert in place without merging.

How does the Case Converter detect word boundaries in an identifier?

It splits on existing camelCase transitions, acronym runs, and separators like underscores, hyphens, dots and slashes, then rebuilds the words in your chosen style.

Can I use it to slugify a title into kebab-case?

Yes. Paste your title, choose kebab-case, and the converter lowercases the words and joins them with hyphens to produce a clean URL slug.

Is my text kept private when I use this tool?

Yes. The Case Converter runs entirely in your browser, so the text you paste is processed locally and never leaves your device.

Case Converter

Convert text between camelCase, snake_case, kebab-case, PascalCase and more.

Your text is converted locally in your browser and nothing is uploaded to a server.

Generating TypeScript types? Try JSON to TypeScript.

About Case Converter

This case converter transforms text between camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, dot.case, path/case, Title Case, Sentence case, lower case and UPPER CASE in one click. It is built for developers renaming variables, API fields and database columns, plus writers and QA engineers who need consistent identifiers or readable headings. Paste an identifier, a CSV column name or a whole list and pick the target style; each line is converted independently, so multi-line lists stay aligned. Use it to turn a JSON key into a constant, slugify a title into kebab-case, or normalize mixed naming conventions across a codebase when converting camelCase to snake_case. Everything is processed locally in your browser, so your data never leaves your device and nothing is tracked.

Features

Converts between 11 styles: camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, dot.case, path/case, Title Case, Sentence case, lower and UPPER
Detects word boundaries from existing camelCase, acronyms, underscores, hyphens, dots and slashes
Converts each line independently, so pasted lists and column names stay perfectly aligned
Strips stray punctuation and collapses separators to produce clean, predictable identifiers
Handles acronym runs like HTTPRequest by splitting them into sensible words
Splits at digit-to-letter transitions so values like item2Name become item2 name
Instant conversion as you type or paste, with one-click copy of the result
Runs entirely in your browser with no tracking of what you paste

How to use the Case Converter

Paste or type your text into the input box.
Choose a target case such as snake_case, camelCase or kebab-case.
Read the converted result in the output panel.
Click Copy to put the converted text on your clipboard.

Example

Input

helloWorld
HTTPRequestHandler

Output

hello_world
http_request_handler

Converting two camelCase identifiers to snake_case, one per line.

Common errors & troubleshooting

Acronyms like HTTPRequest split in an unexpected place. — The converter treats a run of capitals followed by a capital-plus-lowercase as a boundary, so HTTPRequest becomes 'http request'. Add a manual space if you need different grouping before converting.
Numbers get separated from their words. — A lowercase or digit followed by an uppercase letter starts a new word, so 'item2Name' becomes 'item2 name'. Reformat the input if you want the number kept distinct.
Punctuation or emoji disappears from the result. — Only letters, numbers and word separators are kept; other characters are dropped to keep identifiers valid. Use Title or Sentence case on plain prose if you need punctuation preserved.
A multi-line list collapses into one line. — Keep each item on its own line in the input; the tool converts line by line and preserves line breaks in the output.

Frequently asked questions

What is the ArrayKit Case Converter?: It is a text case converter that rewrites words and identifiers between camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, dot.case, path/case, Title Case, Sentence case, lower case and UPPER CASE.
How do I convert camelCase to snake_case?: Paste the camelCase text, choose snake_case as the target, and the Case Converter inserts underscores at each word boundary, for example helloWorld becomes hello_world.
Can I convert a whole list of items at once?: Yes. Each line is converted independently, so you can paste a column of names or identifiers and they all convert in place without merging.
How does the Case Converter detect word boundaries in an identifier?: It splits on existing camelCase transitions, acronym runs, and separators like underscores, hyphens, dots and slashes, then rebuilds the words in your chosen style.
Can I use it to slugify a title into kebab-case?: Yes. Paste your title, choose kebab-case, and the converter lowercases the words and joins them with hyphens to produce a clean URL slug.
Is my text kept private when I use this tool?: Yes. The Case Converter runs entirely in your browser, so the text you paste is processed locally and never leaves your device.

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