Highlight Letters in Text

Want to quickly highlight specific letters in a block of text? The Highlight Letters in Text Tool lets you visually emphasize any letters you choose (like vowels or initials), updating live as you type. It’s perfect for stylizing words, teaching letter recognition, or analyzing frequency patterns in writing.

Paste your input above or import a file below.
No file chosen
Supported file types: .txt, .csv, .json, .html, .xml, .log, .yaml, .css
Total characters: 0
Options

How to Use:

  1. Paste or type your content into the Input Text box.
  2. (Optional) Click Choose File to load a .txt, .csv, .html, or other text-based file.
  3. In the Options box, enter the letters you want to highlight (for example, aeiou).
  4. Matching letters will be wrapped in yellow highlights inside the Highlighted Output box.
  5. Click Copy Output to copy the result as plain text, or Export to File to save the output to a .txt file.
  6. Click Clear All to reset everything and start fresh.

What Highlight Letters in Text Tool can do:

This tool lets you define a custom set of letters and then highlights every matching character in the input. It handles case-insensitive matches, preserves all other text formatting, and updates the result live with a flash animation. It’s great for teaching, testing, visual effects, and live demonstrations of letter distribution.

Example:

Input:

Highlight every vowel in this sentence for clarity.

Letters to Highlight:

aeiou

Output:

H<i>i</i>ghl<i>i</i>ght <mark>e</mark>v<mark>e</mark>ry v<mark>o</mark>w<mark>e</mark>l <mark>i</mark>n th<mark>i</mark>s s<mark>e</mark>nt<mark>e</mark>nc<mark>e</mark> f<mark>o</mark>r cl<mark>a</mark>r<mark>i</mark>ty.

Total characters:

54

Common Use Cases:

Educators use this tool to help students identify vowel usage or consonant clusters. Writers and editors use it to spot repeated letters or letter patterns. It’s also handy for stylized effects in online content or preparing data for phonics and literacy games. Just type, highlight, and export it’s fast and easy.

Useful Tools & Suggestions:

If you’re already focusing on characters, Highlight RegExp Matches in Text gives you more control by letting you target specific patterns, not just single letters. And when you want to scale that up a bit, Highlight Words in Text helps call out full terms instead great for emphasis or analysis.

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