Vowel Replacer

Replaces every vowel, a, e, i, o, and u in either case, with a chosen replacement character, useful for creating stylized or obfuscated text, word puzzles, or quick readability experiments. A free online tool from Staaarter, right in your browser.

Runs locallyUpdated 2026-07-23

Overview

Introduction

Swapping out every vowel in a passage of text for a different character by hand is slow and error-prone once the text gets longer than a sentence or two.

It runs entirely client-side, so nothing you paste is ever uploaded to a server.

What Is Vowel Replacer?

A vowel replacer that swaps every vowel, a, e, i, o, and u in either case, for a chosen replacement character.

It runs entirely client-side as part of this site's String Tools collection, so nothing you paste is ever uploaded to a server.

How Vowel Replacer Works

The tool scans the input with a regular expression matching any of the ten upper- or lowercase vowel characters and replaces each match with the chosen replacement string.

The transformation happens synchronously in JavaScript the moment you type, with no network round trip involved.

When To Use Vowel Replacer

Use it to create stylized or obfuscated text, build a word puzzle where vowels are hidden, or experiment with how readable text stays once vowels are removed or altered.

It's a fast way to get the answer without opening a code editor, a REPL, or writing a one-off script just to check.

Often used alongside Vowel Remover and Vowel Duplicator.

Features

Advantages

  • Supports any replacement string, not just a single character.
  • Leaves consonants, spaces, and punctuation completely untouched.

Limitations

  • Doesn't treat 'y' as a vowel, matching the standard five-vowel definition.

Examples

Replacing vowels with a symbol

Input

hello world

Output

h*ll* w*rld

Every 'e' and 'o' is replaced by the default '*' character; consonants and spaces are unchanged.

Best Practices & Notes

Best Practices

  • Use a single visually distinct character as the replacement to keep the output easy to scan.

Developer Notes

The transform is a single `input.replace(/[aeiouAEIOU]/g, replacement)` call, so it inherently treats every vowel occurrence identically regardless of case, and the replacement string can be arbitrary length since `String.prototype.replace()` handles substitution without a fixed-width constraint.

Vowel Replacer Use Cases

  • Creating stylized or obfuscated display text
  • Building a vowel-hiding word puzzle
  • Experimenting with text readability when vowels are altered

Common Mistakes

  • Expecting 'y' to be treated as a vowel; it's intentionally excluded.
  • Leaving the replacement field empty, which the tool rejects.

Tips

  • Combine with the Consonant Replacer to see both halves of the letter split rendered separately.

References

Frequently Asked Questions