Text Diff Checker

Compare text and find differences instantly. All processing happens locally in your browser—your data is never uploaded, stored, or sent to a server.

Text Difference Checker – SynetrixTools

Quick Samples

📄 Original Text 0 chars

✏️ Modified Text 0 chars

Comparison Options

Ignore Case Ignore Whitespace Ignore Punctuation Ignore Blank Lines Show Line Numbers

Diff Mode:

Granularity:

Context Lines:

🔒

Private by design: All comparison is performed locally in your browser. Files (TXT/DOCX/PDF) are parsed client-side and never uploaded. URL fetches go directly from your browser to the address you provide.

📊 Diff Results

Added

Removed

Changed

Unchanged

No changes

🔍 Enter text in both panels and click Compare Texts to see the diff.

Similarity Score

—

Compare texts to see similarity

Statistics

Lines Added

—

Lines Removed

—

Lines Changed

—

Unchanged

—

Original Lines

—

Modified Lines

—

Orig. Chars

—

Mod. Chars

—

Words (Original) —

Words (Modified) —

Char Delta —

💡 Tips

🔵Use Side by Side for a clear visual split of old vs. new.
🔵Use Unified mode for a compact, patch-style view.
🔵Word-level granularity highlights exactly which words changed.
🔵Enable Ignore Case when comparing text that may differ only in capitalization.
🔵Use Accept/Reject to build a clean merged version of both texts.
🔵Very large documents automatically switch to a lighter line-only diff for speed.
🔵All processing is local — your text never leaves your browser.

❓ Frequently Asked Questions

What is a text diff? ▼

A text diff (short for "difference") is a comparison between two versions of text that highlights what was added, removed, or changed. It's widely used in software development (e.g. Git), document editing, and content review workflows to track changes between revisions.

What is the difference between line, word, and character diff? ▼

Line diff compares entire lines — the standard for code and config files. Word diff breaks each line into words and highlights individual word changes, useful for prose. Character diff goes even further, highlighting every single character that changed — ideal for spotting subtle typos or punctuation differences.

What is a unified diff / patch file? ▼

A unified diff (or patch file) is a standardized text format that represents changes between two files. Lines prefixed with + were added, lines with - were removed, and unmarked lines provide context. Patch files can be applied directly with tools like git apply or the Unix patch command.

Can I upload Word or PDF files? ▼

Yes. TXT, DOCX, and PDF files are supported. Text is extracted entirely in your browser (DOCX via a client-side parser, PDF via PDF.js) — the file itself is never uploaded to a server. Formatting such as tables, images, and complex layouts is not preserved; only the raw text is extracted for comparison.

How does Accept/Reject merging work? ▼

After comparing, open the "Accept / Reject & Merge" panel. For every added, removed, or changed line you choose to keep the original or the modified version. Once you've made your choices, click "Build Merged Output" to generate a single combined document you can copy or download.

Is my text sent to a server? ▼

No. All comparison, file parsing, and merging happens entirely in your browser using JavaScript. Your text is never transmitted to any server, stored in a database, or logged in any way. If you use the "Fetch URL" option, that request goes directly from your browser to the address you provide.

How is the similarity score calculated? ▼

The similarity score is based on the ratio of unchanged lines to total lines across both texts. A score of 100% means the texts are identical; 0% means they share no common lines. It provides a quick at-a-glance measure of how much the two versions differ.

[adinserter name="Page Sidebar Ad Block"]