Inverse Case Converter

What Is an Inverse Case Converter?

An inverse case converter changes the capitalisation of text by swapping uppercase letters with lowercase letters and lowercase letters with uppercase letters. For example, Hello World becomes hELLO wORLD.

This is useful when text has been accidentally capitalised incorrectly, when you need to deliberately reverse letter case, or when you are working with text that needs its existing capitalisation pattern inverted. The converter can process individual words, sentences, paragraphs or larger blocks of plain text.

Why Use an Inverse Case Converter?

Manually changing every uppercase and lowercase letter can be tedious and error-prone. An inverse case converter performs the transformation automatically while leaving the rest of your text structure intact.

How to Use the Inverse Case Converter

Inverting text case takes only a few seconds. The tool changes the case of letters without requiring any manual editing.

1. Enter your text — Type or paste the text you want to change into the input box.
2. Invert the case — Click the Invert Case button to swap uppercase and lowercase letters.
3. Review the result — Check the converted text displayed in the result box.
4. Copy or download — Copy the result to your clipboard or save it as a plain-text file.

Convert and Invert Text Case Online

An inverse case converter, sometimes called an invert case converter or swap case converter, reverses the current capitalisation of letters. Every lowercase letter is changed to uppercase, while every uppercase letter is changed to lowercase. Characters that do not have an uppercase or lowercase form remain unchanged.

For example, the text This Is A Test! becomes tHIS iS a tEST!. Similarly, HELLO world 123 becomes hello WORLD 123. The numbers, spaces and punctuation remain in their original positions.

Inverse Case vs Other Text Case Converters

Inverse case is different from lowercase, uppercase, sentence case and title case. A lowercase converter makes all applicable letters lowercase, while an uppercase converter makes them uppercase. Sentence case and title case apply formatting rules to the text. Inverse case instead looks at each letter's existing case and swaps it with the opposite case.

When to Use Inverse Case Conversion

Inverse case conversion can be useful for correcting text with reversed capitalisation, experimenting with typography, transforming sample text, preparing content for testing and checking how text behaves when letter case is changed. It can also be useful when a block of text has been entered with Caps Lock enabled or otherwise contains unwanted capitalisation.

How Inverse Case Conversion Works

The converter examines each character in the supplied text. If a character has an uppercase form, it is changed to its lowercase form. If it has a lowercase form, it is changed to its uppercase form. Characters such as spaces, numbers and punctuation are left unchanged.

The conversion is performed directly in your browser using JavaScript. The tool does not need to upload your text to a server to perform the case conversion. Because inverse conversion operates on the existing case of each letter, it does not attempt to determine whether a word is a proper noun, acronym, title or sentence.

Frequently Asked Questions