Convert Case

Convert text between every case format you will ever need

Letter case looks trivial until you are staring at a headline that was accidentally typed in all caps, a database column full of inconsistent names, or a JSON key that needs to be converted from snake_case to camelCase for a frontend. This Convert Case tool handles every common case format in a single click — UPPERCASE, lowercase, Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case, dot.case, CONSTANT_CASE, aLtErNaTiNg case, and inverse case.

How to use the converter

Drop in your headlines, variable names, or any text block, choose the target format from the dropdown, and click Convert. The result appears instantly. You can copy the output with one click, clear the input, or process another block of text right away. There is no character limit, no signup, and no daily quota.

The case formats explained

UPPERCASE converts every letter to its capital form. Useful for emphasis, legal headings, formal acronyms, or styling buttons in UI mockups. lowercase does the opposite and is the safe default for URLs, email addresses, tags, and filenames where case can cause matching errors.

Title Case capitalises the first letter of each significant word, which is the standard for book titles, article headlines, and chapter names. Different style guides have slightly different rules about whether short words like "the", "a", "of", "and" should be capitalised — our converter follows the common AP-style convention of lowercasing those small words unless they begin or end the title.

Sentence case capitalises only the first letter of the first word and any proper nouns are kept untouched. This is the most natural style for body copy, UI labels, and modern web content because it reads more like normal speech than aggressive headline styling.

camelCase joins words together, capitalising every word after the first: thisIsCamelCase. It is the JavaScript and Java convention for variable and function names. PascalCase is identical but also capitalises the first word: ThisIsPascalCase — used for class names in most object-oriented languages and React component names.

snake_case separates words with underscores: this_is_snake_case. Python prefers it for variables and functions. kebab-case uses hyphens instead: this-is-kebab-case, and is the standard for URL slugs, CSS classes, and HTML attributes. CONSTANT_CASE is uppercase snake_case used almost exclusively for environment variables and program constants.

Real-world examples

Fixing accidental caps lock. Everyone has typed half a paragraph in caps before realising the lock was on. Paste it in, pick Sentence case, done — no need to retype anything.

Generating URL slugs. Take a blog post title, convert it to lowercase, then to kebab-case to get a clean, SEO-friendly URL slug like how-to-bake-sourdough-bread.

Refactoring code. Migrating a Python codebase that uses snake_case variables to a JavaScript frontend that expects camelCase? Convert your variable names in bulk instead of doing it by hand.

Stylising social media bios. Title case adds a professional touch to LinkedIn headlines. AlTeRnAtInG case is occasionally used for ironic or sarcastic effect in social posts.

Database normalisation. Column values like product categories or country names imported from multiple sources often have inconsistent casing. Run them through lowercase or Title Case once and you can de-duplicate properly.

Why case sensitivity matters more than you think

On most operating systems and most databases, Email and email are considered different strings. That means a duplicate-removal pass will keep both unless you normalise case first. URL paths, JSON keys, hashtag matching, and full-text search can all behave unexpectedly when case is inconsistent. Running a quick lowercase pass before any data-cleanup operation prevents a class of bugs you will not see until production.

Privacy and how this works

Every conversion runs in your browser using standard JavaScript string methods. Nothing is sent to a server, nothing is stored, and nothing is logged. You can disconnect from the internet after the page loads and the tool will still work. That makes it safe to convert confidential documents, internal naming conventions, or anything else you do not want a third party to see.