# Text Diff - Online Text Comparison / Diff Tool

> Free online text diff tool: compare two texts line by line, highlight added and removed lines, and optionally ignore case and trailing spaces. Runs locally.

- URL: https://qilingtools.com/en/text-diff
- Category: Developer Tools (https://qilingtools.com/en/dev)
- Tags: [Text](https://qilingtools.com/en/tags/text), [Developer](https://qilingtools.com/en/tags/dev)
- Last updated: 2026-11-11
- Price: Free, no sign-up
- Privacy: Runs locally in the browser; files are never uploaded

Compare two blocks of text line by line to find added, removed and unchanged lines with color highlighting. Built on a longest-common-subsequence algorithm for clear results. Optionally ignore case or leading/trailing whitespace. Great for checking copy changes, config differences and code snippets, all locally.

## How to use

1. Paste the original text on the left
2. Paste the changed text on the right
3. Read the highlighted diff below

## Features

- Line diff: green added, red removed
- LCS-based for accurate alignment
- Ignore case and trailing spaces
- Counts added/removed lines, runs locally

## FAQ

### Can it compare Word or PDF?

This tool compares plain text. Copy the content out as text first, then paste it in.

### Is it line or character based?

Line based, which fits most copy and code cases; a small in-line change shows as a removed line plus an added line.

### Are my files or data uploaded?

No. Everything runs locally in your browser with no network upload, and is discarded when you close the page.

### Do I need to sign up or pay?

No. The site is completely free, needs no account and has no usage limits.

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