Text Compare
Compare two texts and find differences
What is Text Compare?
Text Compare is a free online diff tool that lets you compare two texts side by side and instantly see the differences between them. It highlights additions, deletions, and modifications at the line level, making it easy to spot exactly what changed between two versions of a document. This tool is invaluable for comparing code versions, reviewing document revisions, checking translated text against originals, verifying data consistency, and auditing configuration file changes. The comparison algorithm provides clear visual indicators with color-coded highlighting: green for additions, red for deletions, and yellow for modifications. You can paste any text including code, prose, configuration files, or data dumps. All processing happens entirely in your browser, so sensitive documents are never transmitted to any server. Whether you are a developer reviewing code changes, an editor tracking revisions, or a QA engineer validating deployments, Text Compare gives you instant visibility into the exact differences between any two pieces of text.
How to Use
- Enter the original text on the left.
- Enter the modified text on the right.
- Click 'Compare' to see differences highlighted with colors.
Tips & Best Practices
- Paste the original text on the left and the modified text on the right for the most intuitive comparison.
- Use this tool to verify copy-paste accuracy when moving text between documents or systems.
- Compare configuration files before and after changes to ensure only intended modifications were made.
- For code reviews, compare the old and new versions to quickly identify all changes.
- When checking translations, compare the original and translated text to ensure no sections were accidentally omitted.
Use Cases
Code Review
Compare two versions of source code to see exactly what lines were added, removed, or modified.
Document Editing
Track changes between draft versions of articles, contracts, or reports without needing Word's track changes feature.
Configuration Audit
Compare server configuration files before and after deployment to verify only intended changes were applied.
Translation Verification
Compare original and translated documents to ensure completeness and catch missing sections.
FAQ
How does text comparison work?
It compares two texts line by line, highlighting added, removed, and unchanged lines with different colors. It uses the LCS (Longest Common Subsequence) algorithm.
Can I compare large texts?
Yes, but very large texts (thousands of lines) may take longer to process. All processing is done in the browser.
What is the LCS algorithm?
LCS (Longest Common Subsequence) finds the longest subsequence common to two sequences, and it is the core algorithm behind diff tools.
Is my data collected?
No, all comparison processing happens in your browser and no text is sent to any server.
What do the different colors mean?
Red indicates removed lines, green indicates added lines, and gray indicates unchanged lines.
Are whitespace differences detected?
Yes, differences in spaces and tabs are detected. Trailing whitespace differences are also shown as changes.
Is the comparison case-sensitive?
Yes, the comparison is case-sensitive by default. 'Hello' and 'hello' will be flagged as different.
Can I compare code files?
Yes, you can compare any text including source code. Paste the old version on the left and the new version on the right.
What do the colors mean?
Green highlights indicate added lines, red highlights indicate deleted lines, and yellow highlights indicate modified lines.
Is there a size limit for comparison?
There is no hard limit, but very large texts may take longer to process since everything runs in your browser.
Can I compare files directly?
Copy the contents of each file and paste them into the two text areas. The comparison will run automatically.
Does it detect moved lines?
The tool compares line by line in order, so moved lines will appear as deletions in the original position and additions in the new position.