Inverse Case Converter
Swap the case of every letter in your text. Uppercase becomes lowercase and lowercase becomes uppercase, instantly and online.
An inverse case converter flips the case of every letter: capitals become lowercase and lowercase letters become capitals. Digits, spaces, and punctuation are left untouched.
Examples
| Input | Output |
|---|---|
| Hello World | hELLO wORLD |
| iPhone 15 Pro | IpHONE 15 pRO |
When to use the inverse case converter
The overwhelmingly common reason to invert case is a caps lock accident: you typed a paragraph with the key engaged and shift held for what should have been the capitals, so every letter came out backwards. Inverting restores the intended text in one pass — something neither uppercase nor lowercase alone can do.
Beyond that repair, inverse case appears in playful contexts: flipping text for emphasis, generating a variant of alternating case that starts with a capital, or producing deliberately awkward-looking strings for testing how an interface handles mixed input.
Unlike lowercasing or uppercasing, inverting is lossless and reversible — run the output through the converter a second time and you get the original text back exactly.
Frequently asked questions
What does inverse case do to numbers and symbols?
Nothing. Only letters have a case to invert, so digits, punctuation, and symbols are copied through unchanged.
Is inverting case reversible?
Yes. Running inverse case twice returns the original text exactly, because each flip is its own opposite. This makes it the safest of the case tools.
How do I fix text typed with caps lock on?
If you held shift for the capitals, inverse case restores it perfectly. If you did not use shift at all, the text is uniformly uppercase — use the sentence case converter instead.