Case Converter

What this case converter does

This English-language case converter handles 11 formats in one tool: UPPERCASE, lowercase, Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, dot.case, and aLtErNaTiNg. Most converters stumble when the input is already camelCase or uses mixed delimiters — type getUserID_v2 into a naive tool and you'll get getuserid_v2. This converter splits on case boundaries first, then by delimiter, so the tokenizer preserves word boundaries regardless of how the input was originally formatted. Every conversion happens locally: 100% client-side — your data never leaves your browser. No uploads, no tracking, no server logs. Whether you're a developer renaming variables, a writer fixing capitalization, or someone building URL slugs, the tool covers the full spectrum of text capitalization needs.

Features

• Smart boundary tokenizer. Splits input on both case boundaries and delimiters (spaces, underscores, hyphens, dots), so mixed inputs like getUserID_v2 or parse-HTML-entity convert cleanly into any target case without losing words.
• 11 case formats. Covers every naming convention used in code and prose: UPPER, lower, Title, Sentence, camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, dot.case, and alternating — no add-ons needed.
• Lowercase and uppercase converter. The classic all-caps converter and lowercase converter are one click away. Useful for shouting in Slack, normalizing database fields, or prepping text for a text.toUpperCase() comparison in JavaScript.
• Title case and sentence case. Title Case capitalizes each principal word following standard editorial conventions. Sentence case capitalizes only the first word, matching the style recommended by many modern style guides including AP and MDN Web Docs.
• Programming case formats. camelCase and PascalCase for JS/Java/Swift, snake_case for Python, CONSTANT_CASE for environment variables, kebab-case for CSS and URL slugs. Pairs naturally with the [URL slug generator](/en/slugify/) when building route names.
• One-click copy. Hit Copy after any conversion and the result lands on your clipboard instantly. Clear resets both input and output so you can start a new batch without a page reload.

How to use the case converter

Paste your text, pick a target case, and the output updates immediately. No button to submit.

1. Paste your text. Drop any string into the input field — a sentence, a variable name, a headline, or multi-line content. The tool accepts camelCase, snake_case, plain prose, and everything in between.
2. Choose a case format. Select the target from the dropdown. For Python-to-JavaScript ports, switch from snake_case to camelCase. For environment variables, pick CONSTANT_CASE — equivalent to text.upper().replace(' ', '_') in Python.
3. Copy the result. Click Copy to send the converted text to your clipboard, then paste it directly into your editor, CMS, or terminal. Use Clear to reset for the next string.

Common use cases

• Porting code between languages. Python uses snake_case by convention; JavaScript uses camelCase. When porting a module, paste your Python identifiers and switch to camelCase in one pass instead of renaming each variable by hand.
• Generating URL slugs. Turn an article title like 'Getting Started With Astro' into getting-started-with-astro using kebab-case. For more slug-specific options, the [URL slug generator](/en/slugify/) handles Unicode normalization and stop-word removal.
• Creating environment variable names. Config keys written in plain English become CONSTANT_CASE environment variable names instantly. database connection timeout becomes DATABASE_CONNECTION_TIMEOUT without manual editing.
• Fixing headline capitalization. Paste a draft headline and apply Title Case to match your publication's style guide, or switch to Sentence case for a more conversational tone — common in technical documentation from teams in Austin to London.
• Normalizing user input. Before storing or comparing strings, developers often need a consistent case. Use the lowercase converter to preview how text.toLowerCase() will behave on a real sample before wiring it into your validation logic.

Frequently asked questions