Character Compare – Character‑Level Diff
See exactly which characters were added or removed between two texts. Our tool highlights every single change, making it perfect for proofreading, reviewing small code edits, or checking for hidden whitespace differences. Everything runs in your browser — no signup, no uploads.
Why use a character‑level diff?
Sometimes a word‑level or line‑level comparison isn't enough. If you need to catch a single wrong letter, a missing space, or a curly quote that should be straight, this tool shows you exactly what changed at the character level. It's especially useful for proofreaders, developers, and anyone dealing with precise text comparisons.
- Pinpoint accuracy – see every added and deleted character, highlighted in green (additions) and red with strikethrough (deletions).
- Case‑sensitivity toggle – flip between strict and relaxed matching with one click.
- Instant feedback – the diff updates live as you type (after a short debounce) or when you click Compare.
- Privacy first – all processing is done locally; your texts never leave your device.
How to compare characters (step‑by‑step)
1. Enter your texts
Paste the original text in the left box and the modified text in the right box.
2. Set case sensitivity
By default, the comparison is case‑sensitive. Uncheck the box if you want "A" and "a" to be considered the same.
3. View the diff
Green characters were added, red characters (with strikethrough) were deleted, and unchanged text stays neutral.
4. Copy or clear
Click "Copy diff text" to grab the diff as plain text with +/- markers, or "Clear all" to start over.
Example: a tiny typo caught
| Original | Modified | Diff (visual) |
|---|---|---|
| Helllo World | Hello World! | HellHellllo World! |
Common use cases
- Proofreading: Compare a draft with the final version to confirm only intended changes were made.
- Code review: See exactly which characters changed in a config file or small script.
- Whitespace audit: Catch invisible trailing spaces or mixed tabs/spaces that other tools miss.
- Encoding issues: Spot when smart quotes, em dashes, or other special characters were accidentally changed.
- Before/after transformations: Check that a text transformation (e.g., case change, symbol replacement) produced the expected result.
Pro tips
- For longer texts, the diff can become busy. Try narrowing the comparison to the specific paragraph or sentence you're interested in.
- If you want a higher‑level overview first, use our Text Diff Checker (line‑by‑line) or Word Compare, then drill down with this tool.
- The plain‑text copy output uses "+" for additions and "-" for deletions, making it easy to read in any text editor.