How to Change Text Case (Without Retyping It)

Four cases, no dropdown

Most converters make you pick a mode before you've decided what you want. This one shows all four at once, which costs nothing and puts Title Case and Sentence case next to each other — genuinely the thing most people are trying to work out when they arrive.

The text never leaves your browser.

THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG. IT WAS WORTH WATCHING.

the quick brown fox jumps over the lazy dog. it was worth watching.

The Quick Brown Fox Jumps Over The Lazy Dog. It Was Worth Watching.

The quick brown fox jumps over the lazy dog. It was worth watching.

What each one does

Take the QUICK brown Fox jumps over the lazy dog. it was worth watching.

The two things to check before you paste

Both are worth understanding, because they're the reason you can't paste the output straight into a document.

Title Case capitalises everything, including "The" and "Over"

Real title styles don't. Most leave short words — a, an, the, of, in, on — lowercase unless they open the title. But the major style guides disagree with each other about which words qualify and how short is short.

A converter can't apply a style guide you haven't named. So the output is a starting point: fix the small words by eye, and whichever way you decide, be consistent — consistency is worth more than picking the "right" guide.

Sentence case can't tell an abbreviation from a full stop

It does capitalise each sentence — the rule is "a ., ! or ? followed by a space." That works on ordinary prose.

It breaks on abbreviations, because an abbreviation is a full stop followed by a space:

Telling approx. from the end of a sentence means understanding the words, not transforming the characters. So the honest trade is a rule that's right on normal text and predictable when it's wrong — you know to check after an abbreviation.

The space requirement is what keeps it safe everywhere else. A decimal has no space after the point, so the meeting is at 3.50 today comes back untouched. Same for one.two.three.

The proper-noun problem

This one catches people out. Run london in MARCH through it:

Sentence case lowercased march. It has no way to know that's a month rather than a verb, or that London is a place.

Transforming letters is easy; understanding text is not. Proper nouns are the one thing you'll always put back by hand — scan for them before pasting the result anywhere that matters.

Where each case belongs

• Body text → Sentence case, always
• Headlines → Title or Sentence, per your style guide — pick one and hold it
• Buttons and labels → Sentence case; it's measurably easier to read
• Acronyms → UPPERCASE, the one solid use for it
• Whole paragraphs in capitals → don't

That last one isn't just etiquette. Text set entirely in capitals is slower to read, because the distinctive word shapes that let you recognise words at a glance all flatten into identical rectangles. It also reads as shouting nearly everywhere.

Nothing is uploaded

Worth stating plainly, because of what people actually paste into case converters: half-finished emails, draft contracts, client lists, other people's names.

This runs entirely in your browser through a fixed list of allowed text operations. There's no upload, no server call, and nothing stored. Close the tab and it's gone.

What about camelCase and snake_case?

Not here. Those are programming identifier conventions rather than text cases — they have to break words apart and rejoin them with different separators, not just change letters. A URL slug is the nearest shape this site offers.

Print the text case reference if you're the person on your team who keeps being asked which case the buttons use.