Side-by-Side Text Comparison
Compare texts in a split-screen view to easily spot changes per line.
✨ Upgraded Tool Available
We've built a more powerful version of this tool with advanced features including Inline/Split Views, Word/Line/Char Modes, Sort Lines, Ignore Case, and HTML Export.
Try Compare Two TextsVisual Line-by-Line Text Comparison
The Side-by-Side Text Comparison tool provides a clear, visual representation of differences between two text versions. With color-coded highlighting and parallel display, you can quickly identify what changed, what was added, and what was removed—perfect for document reviews, code audits, and version control.
Key Features
Color-Coded Diffs
Red for deletions, green for additions. Instantly spot changes at a glance.
Line Numbers
Track exact line positions for precise change tracking and references.
File Upload
Upload text files directly. No need to copy-paste large documents.
Export Report
Download comparison as HTML for sharing or archiving.
100% Private
All processing happens in your browser. Your data never leaves your device.
Mobile Ready
Responsive design works perfectly on smartphones and tablets.
Common Use Cases
Code Reviews
Compare before and after versions of source code files. Perfect for reviewing pull requests, tracking bug fixes, or auditing refactoring changes with precise line-by-line accuracy.
Document Versioning
Track changes in contracts, legal documents, reports, or manuscripts. See exactly what was modified between drafts, ensuring no important changes are missed.
Content Editing
Review editorial changes in articles, blog posts, or essays. Writers and editors can clearly see what content was added, removed, or modified during the revision process.
Configuration Audits
Compare configuration files (nginx.conf, .env, package.json) before and after updates. Verify that only intended changes were made and catch accidental modifications.
How to Use
- Paste or Upload Original: Enter your original text in the left box, or click "Upload" to load a file.
- Paste or Upload Modified: Enter your modified text in the right box, or upload the updated version.
- Review Differences: The tool automatically highlights changes: red for deletions (left), green for additions (right).
- Use Line Numbers: Reference specific lines to discuss or document changes with your team.
- Download Report: Click "Download Report" to save the comparison as an HTML file for archiving or sharing.
Frequently Asked Questions
What is the Side-by-Side Text Comparison tool?
The Side-by-Side Text Comparison tool is a free online utility that displays two versions of text in parallel columns, highlighting differences line-by-line with color coding. Deleted lines appear in red on the left side, added lines appear in green on the right side, and unchanged lines appear in gray on both sides. Line numbers help you track exact positions of changes.
How does the color-coding system work?
The tool uses a clear color-coding system: Red highlighting indicates deleted lines (appears only on the left/original side), green highlighting shows added lines (appears only on the right/modified side), and gray text represents unchanged lines (appears on both sides). Each line includes a line number for precise reference.
Can I upload files for comparison?
Yes! Click the 'Upload' button above each text box to load files from your computer. The tool accepts text files (.txt), markdown files (.md), and other plain text formats. Both the original and modified versions can be uploaded separately for easy comparison.
How do I download the comparison results?
After comparing your texts, click the 'Download Report' button located below the comparison table. This saves the side-by-side comparison as an HTML file that you can open in any web browser, share with team members, or archive for future reference.
What are the best use cases for this tool?
This tool is ideal for: (1) Code reviews - comparing different versions of source code, (2) Document versioning - tracking changes in contracts, reports, or manuscripts, (3) Content editing - reviewing editorial changes in articles or essays, (4) Configuration audits - comparing config files before and after updates, (5) Translation comparison - checking differences between language versions.
Is my data secure when using this tool?
Absolutely. All text comparison happens entirely in your web browser using client-side JavaScript. Your text never leaves your device or gets uploaded to our servers. This ensures complete privacy and security for sensitive documents like contracts, code, or confidential content.
How is this different from Compare Two Texts tool?
This tool focuses on simplicity with a pure side-by-side view. The Compare Two Texts tool offers advanced features like inline/split view modes, word/line/character-level comparison, sort lines, ignore case options, similarity percentage, and enhanced export formats (HTML/Markdown). For basic line-by-line visual comparison, use this tool. For advanced analysis, use Compare Two Texts.
Can I compare code files?
Yes! The tool works perfectly for comparing code files in any programming language (JavaScript, Python, Java, etc.). The monospace font and line numbers make it easy to spot exactly which lines of code were added, removed, or modified. Upload your before and after code files to see the differences clearly.
Does it work on mobile devices?
Yes, the tool is fully responsive and works on smartphones and tablets. On mobile devices, the side-by-side view automatically stacks vertically for easier reading, while maintaining all color-coding and line number features for accurate comparison on smaller screens.
What file size limits are there?
Since all processing happens in your browser, the practical limit depends on your device's memory. For optimal performance, we recommend files under 1MB (approximately 15,000 lines). Larger files may work but could cause slower performance. For very large file comparisons, consider using desktop diff tools.