Side-by-Side Diff Viewer — GitHub Style Comparison

Compare two versions of text or code side-by-side. Identify changes, track edits, and visualize added or removed lines just like GitHub.

Original Content
Original Content
Updated Content
1const a = 21;
2console.log(a);
1const a = 12;
2console.log(a);
Diff Statistics
1Added Lines
1Removed Lines
1Unchanged Lines

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Compare Code or Text Side-by-Side

ToolMateX’s Side-by-Side Diff Viewer lets you compare two blocks of text or source code in a visually clean layout inspired by GitHub. It highlights:

  • 🔴 Removed lines (left column)
  • 🟢 Added lines (right column)
  • 🟡 Word-level inline highlights for changed lines
  • 🔢 Matching line numbers to stay aligned
  • 🧠 Fully browser-based — fast and private

Perfect for Developers and Writers

This tool is ideal for:

  • 🧑‍💻 Code review workflows
  • 📝 Proofreading content revisions
  • 📚 Markdown or HTML content comparison
  • 🛠 Debugging outputs or logs

How It Works

  1. Paste original and modified content
  2. See line-by-line comparison instantly
  3. Changed lines show word-level differences
  4. All lines, including unchanged ones, are retained for context

Why Choose ToolMateX's Diff Viewer?

  • ✅ GitHub-style layout with real-time updates
  • ✅ Word-level inline changes
  • ✅ No login or upload required
  • ✅ Ideal for any file format: JS, Python, HTML, Markdown, JSON, etc.

Example Use Cases

  • Compare configuration files (e.g., JSON, YAML)
  • Check what changed in code during a bug fix
  • Preview blog post revisions before publishing
  • Compare CSVs, notes, or logs quickly

Frequently Asked Questions (FAQs)

Why Use ToolMateX

Tired of bloated tool websites with 10 ads per click? This platform is built for speed, simplicity, and reliability. Whether you're debugging JSON or testing colors, we’ve got your back.

Free to Use, Forever
Free to Use, Forever

All tools run right in your browser, fast, reliable, and available whenever you need them. No ads, and nothing to install.

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Works Offline (Most of Them)
Works Offline (Most of Them)

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Made by a 1-Person Team
Made by a 1-Person Team

Made by someone who actually uses these tools daily. It’s fast, clean, and made with your workflow in mind, not corporate KPIs.

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