GT
GenTradeTools

Text Diff Checker

Compare two texts side-by-side with syntax highlighting, unified diff export, and advanced options

Plain Text
Whitespace
Case
Trim
Monaco Diff Editor
Inline Diff
Loading diff editor...

Quick Examples

Features

Monaco Diff Editor

VS Code-powered inline diff with syntax highlighting

Multiple Views

Side-by-side, unified, or inline diff display

Syntax Highlighting

Support for JS, TS, JSON, HTML, CSS, Python, and more

Ignore Options

Ignore whitespace, case, or trim lines

File Upload

Upload files directly for comparison

Export Patch

Download unified diff as .patch file

Statistics

Added, removed, unchanged lines with percentages

Similarity Score

Visual similarity percentage with progress bar

Line Numbers

Synced line numbers across both views

Word Wrap

Toggle word wrap for long lines

Copy Unified Diff

One-click copy in standard diff format

Client-Side

100% browser-based, your data stays private

Developer Tools

Understanding Text Diff

Text diff is the process of comparing two versions of text to identify differences. It's fundamental to version control systems like Git, code review tools, and document comparison applications. The algorithm finds the longest common subsequence (LCS) to determine what was added, removed, or changed.

This tool provides multiple diff views including Monaco Editor's professional inline diff, traditional side-by-side comparison, and unified diff format. Whether you're reviewing code changes, comparing configs, or auditing documents, everything runs locally in your browser.

Common Use Cases

Code Review

Compare versions of code files to review changes before merging or deployment.

Config Comparison

Find differences between configuration files across environments (dev, staging, prod).

Document Auditing

Track changes in contracts, policies, or documentation between revisions.

Merge Conflicts

Understand and resolve merge conflicts by visualizing the differences clearly.

Diff discipline for product teams

How to use the Text Diff checker to police releases, unblock editors, and build trust with auditors who expect reproducible comparisons.

Why text diffing still matters

Every shipped feature triggers downstream review: screenshots for marketing, release notes for compliance, and documentation for customer success. The Text Diff checker brings that scrutiny into the browser so writers, engineers, and localization teams can self-serve answers before tapping an SRE. Because it runs entirely on the client, sensitive drafts stay on your machine while still benefiting from the same Longest Common Subsequence logic your Git server trusts.

Workflows this replaces

Product squads previously exported two versions into a desktop diff tool, took screenshots, and pasted them into bug trackers. That ping-pong inflated cycle time and made non-technical teammates feel blocked. Now editors can run a comparison, toggle unified or side-by-side views, snapshot the stats panel, and drop a link into the incident channel with zero tooling requests. QA leads routinely paste API payloads or legal agreements to highlight single-word changes without pushing code.

Precision controls explained

Whitespace and case toggles ship with conservative defaults so nothing slips through unnoticed. Enable "Ignore whitespace" once translations finish, or toggle it off when indentation carries meaning (YAML manifests or poetry layouts). Case sensitivity matters for auth scopes, DNS entries, and marketing taglines, so treat it as a two-step check: first compare with case preserved, then run a lenient pass to isolate actual copy edits.

Reading the stats block

The statistics grid synthesizes the diff into an executive-friendly format. Added, removed, and unchanged lines display raw counts plus percentages so you know whether churn is cosmetic or structural. Similarity is a single percentage derived from the same math we use in release retro decks. Teams feed those numbers into monitoring dashboards, building a history of how much documentation moved during a sprint and catching unusual spikes that warrant review.

Exporting evidence

The "Copy unified diff" button generates the canonical patch format used by Git, Mercurial, and most code review bots. Designers paste that output into Notion or Jira tickets so reviewers can comment inline. Because everything is plain text, compliance teams can archive the diff alongside contracts without proprietary viewers.

Tips for better comparisons

  • Normalize line endings before pasting so CRLF vs LF does not pollute the removal counts.
  • Use the examples grid when onboarding teammates so they understand how additions, deletions, and neutral lines render.
  • Pair the diff tool with a screen recorder when auditing WYSIWYG editors that quietly inject markup.
  • Add context above each textarea ("Before hotfix", "After localization") so exported screenshots read well in chat.

Incident-ready habits

During a rollback drill, keep one textarea locked to the last good configuration and paste fresh output into the other. The tool becomes a living guardrail because every run produces comparable metrics. Some organizations pin the diff panel on a dedicated monitor during release nights, treating the green similarity badge as a go/no-go indicator alongside load balancer stats.

Looking forward

Next quarters will bring FlowPanel layouts and saved presets, but the principle stands: disciplined diffing is a cultural practice, not a single feature. Embed the Text Diff checker into your Definition of Done and you will spend less time explaining regressions and more time shipping.

FAQ

What diff algorithm is used?

This tool uses the Longest Common Subsequence (LCS) algorithm, similar to what Git and other version control systems use for computing differences.

Can I compare binary files?

This tool is designed for text comparison. Binary files should be compared using specialized tools or by computing their hashes.

What is unified diff format?

Unified diff is a standard format for sharing patches. It shows changes with + and - prefixes, along with context lines, and can be applied using patch utilities.

Is my data secure?

Yes. All comparison happens in your browser. No data is sent to any server—your files and text remain completely private.

LCS Algorithm·100% Client-Side·Privacy First