Online Text Compare & Code Diff Checker

Compare two text documents or code snippets to find differences instantly. Secure, offline text diffing tool with character-level and syntax highlighting.

Share Diff

Generate a public link to share this diff with others.

Note: Text shared publicly will be saved to our servers.

Pro Feature: Save private diffs to the cloud to access them anywhere. Sign in to Upgrade

Introduction

Instantly compare two blocks of code or text side-by-side to find subtle additions, deletions, and typo modifications with perfect character-level accuracy.

What is the Diff Checker and Why Use It?

Finding a missing semicolon or a single changed variable name between two 500-line code files is like looking for a needle in a haystack. Our Online Diff Checker automates this by comparing your original text against your modified text. It highlights exactly what was added (in green) and what was deleted (in red). Ideal for developers reviewing pull requests outside their IDE, copywriters checking document revisions, or anyone needing to spot hidden changes. Executed locally, it is entirely safe for proprietary source code.

Key Features

  • 100% Client-Side Privacy: Source code is highly confidential. Our diffing algorithm runs locally via your browser's JavaScript, ensuring zero data transmission.
  • Character-Level Precision: Doesn't just highlight the changed line; it highlights the exact characters that differ, making spotting typos effortless.
  • Side-by-Side or Inline: Toggle between split-pane viewing for large files, or unified inline viewing for quick checks.
  • Syntax Highlighting: Automatically formats and colors code syntax (HTML, JS, PHP) to make reading easier while comparing.

How to Use the Text Compare Tool (Step-by-Step)

  1. Step 1: Paste your original (baseline) text into the left panel.
  2. Step 2: Paste your modified (updated) text into the right panel.
  3. Step 3: The tool will instantly compute the differences. Use the toolbar to toggle between side-by-side or inline view modes.

Frequently Asked Questions

Absolutely not. We built this tool knowing developers need a secure place to compare unreleased code. Everything is processed natively by your browser.

You can toggle the 'Ignore Whitespace' setting. By default, it tracks spaces and tabs so you can detect formatting changes, but you can disable this to focus solely on logic changes.

Because the tool runs entirely in your local RAM, the limit depends on your device's capacity. However, comparing files up to 50,000 lines is generally instantaneous.