Text Case Converter: UPPERCASE, lowercase, Title Case & More

Fixing the capitalization of text by hand is tedious, whether you are re-typing a headline in Title Case, or converting a label into snake_case for code. A case converter does it in one click. Paste your text on the left, pick a style, and the converted result appears on the right, ready to copy.

The tool covers everyday writing styles, UPPERCASE, lowercase, Title Case and Sentence case, as well as the programmer conventions you reach for daily: camelCase, PascalCase, snake_case, kebab-case, SCREAMING_SNAKE_CASE and dot.case. There are a couple of fun ones too, Reverse and aLtErNaTiNg case. Word and character counts are shown for both boxes so you can see the effect at a glance.

Everything happens locally in your browser, so your text is never uploaded, and there's no limit on how much you convert. Use Swap to push the output back into the input for a second pass, and Download to save the result. Need to size the text too? Open the word counter.

When do you actually need a case converter?

Most people reach for one without planning to. You copy a heading out of a PDF and it lands in your document as one long shout of capital letters. You move a rough draft into a finished piece and the casing is all over the place. A quick paste and one click sorts it out. A few common moments where it saves real time:

• Writers turning an all-caps note back into sentence case that reads normally.
• Developers naming things and needing camelCase or snake_case without retyping each word.
• Text copied from PDFs or scanned files that arrives in full capitals.
• Social media posts, where title case on a headline reads a little more considered.
• SEO work, where a title tag looks best in title case and the meta description in sentence case.
• Legal documents and form fields that ask for a name or reference in ALL CAPS.
• Email subject lines, where title case tends to lift open rates a touch.

The difference between each case type

The labels get mixed up a lot, so here is what each one actually does and where you would use it:

• UPPERCASE: every letter is capital. Good for warnings, acronyms and emphasis. Example: "TERMS AND CONDITIONS".
• lowercase: every letter is small. Common in URLs, usernames and casual messaging. Example: "hello world".
• Title Case: the first letter of each major word is capital. Used for headlines, book titles and article headings. Example: "The Quick Brown Fox".
• Sentence case: only the first letter of the sentence is capital. This is how most body text and descriptions are written. Example: "The quick brown fox".
• camelCase: no spaces, and every word after the first starts with a capital. Standard for JavaScript variables, function names and APIs. Example: "quickBrownFox".
• snake_case: words joined by underscores, all lowercase. Common for Python variables, database column names and file names. Example: "quick_brown_fox".

A quick note on smart case conversion

Plenty of tools change every letter mechanically and call it done. Title case is the tricky one. Small words like "and", "the", "of" and "in" should stay lowercase when they sit in the middle of a title, even though they are still words. This converter follows the standard title rules for those, so a heading comes out publication ready rather than needing a second pass by hand.