Text Diff Checker - Compare Two Texts Online

🔍 Compare Two Texts

Original Text ORIGINAL

Modified Text MODIFIED

Ignore case Ignore extra whitespace Highlight word differences Hide unchanged lines

Diff Result

📖 How to Use the Diff Checker

Paste your original text into the left panel labeled "Original Text".
Paste your modified text into the right panel labeled "Modified Text".
Set options like ignoring case, extra whitespace, or hiding unchanged lines using the checkboxes.
Click "Compare Texts" to run the diff. Results appear instantly below with color-coded highlights.
Switch views between Unified and Side-by-Side using the toggle buttons on the result panel.

ℹ️ About This Tool

The ToolCentrix Diff Checker is a free, browser-based text difference checker that lets you compare two texts side by side and instantly identify what has changed. Whether you're a developer reviewing code changes, a writer comparing document versions, or a student checking edits, this online diff tool has you covered.

Using a line-by-line comparison algorithm, the tool highlights added lines in green, removed lines in red, and keeps unchanged lines neutral. The optional word-level diff further pinpoints exact inline changes within modified lines. You can also toggle between a unified view and a side-by-side view for the most comfortable reading experience.

All processing happens entirely in your browser — your text is never uploaded or stored on any server, ensuring complete privacy. No login, no installation, no limits.

❓ Frequently Asked Questions

What is a diff checker? +

A diff checker is an online tool that compares two pieces of text and highlights the differences between them, showing additions, deletions, and unchanged lines clearly. It's commonly used by developers, writers, and editors to track changes between document versions.

How does the text difference checker work? +

The tool splits both texts into individual lines and compares them using a diff algorithm (LCS — Longest Common Subsequence). Lines added in the second text are shown in green, lines removed from the first text are shown in red, and unchanged lines are shown normally. With word diff enabled, individual word changes are also highlighted within each line.

Is the diff checker free to use? +

Yes, ToolCentrix's diff checker is completely free to use with no registration required. You can compare as many texts as you want without any limitations, watermarks, or paywalls.

Can I compare large documents with this tool? +

Yes, the online diff tool can handle large text documents. Simply paste your text into both panels and click Compare. The tool works entirely in your browser so your text is never sent to any server, making it safe for sensitive documents too.

What types of text can I compare? +

You can compare any plain text including source code, articles, essays, configuration files, emails, legal documents, and more. The diff checker works line by line and also highlights inline word-level differences when the option is enabled.