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Diff & Text Compare

Data & Formatting

Compare two code snippets, configurations, or JSON files line-by-line with visual change highlighting.

Original Text (Left)
Plain Text / Monospace7 lines · 159 chars
Modified Text (Right)
Plain Text / Monospace6 lines · 215 chars
Diff Output
+4 added-5 removed2 unchanged
11 function calculateSprintVelocity(stories) {
2- let total = 0;
3- for (let i = 0; i < stories.length; i++) {
4- total += stories[i].points;
5- }
6- return total;
2+ // Use array reduce for cleaner calculation
3+ return stories
4+ .filter((story) => story.status === "DONE")
5+ .reduce((sum, story) => sum + (story.points || 0), 0);
76 }
Guide & Documentation

Side-by-Side Code, JSON & Text Difference Checker

Compare two text snippets, code files, or API JSON payloads line-by-line. Highlights additions, deletions, and modifications in unified or side-by-side split view directly in your browser.

How to Compare Text Diffs

01

Paste Original & Modified Text

Paste the original code or payload into the left editor and the updated version into the right editor.

02

Choose Comparison View

Switch between a Unified single-column view or Side-by-Side split diff display.

03

Inspect Highlighted Changes

Instantly review green insertions, red removals, and unchanged code blocks with line numbers.

Diff Checker Features

Side-by-Side & Unified Modes

Flexible visualization adapting to wide desktop monitors or compact laptop screens.

Zero-Knowledge Local Computation

Processing happens entirely on your machine via JavaScript; sensitive credentials or code never touch our servers.

Sample Data & Instant Swap

Quickly test refactoring differences or swap left and right inputs with a single click.

Code Diffing Best Practices

  • §1Format JSON or code with consistent indentation before running diffs to avoid noisy whitespace changes.
  • §2Review large configuration diffs carefully before deploying to staging or production environments.
  • §3Ensure secrets, database passwords, and API keys are redacted before sharing diffs with colleagues.

Frequently Asked Questions

Is my code secure and private?
Yes. The diff algorithm runs client-side in your browser. No text, code, or data is uploaded or transmitted anywhere.
Can I compare large files?
Yes, the in-memory Myers diff implementation handles thousands of lines of code efficiently.
Can I compare formatted JSON payloads?
Yes! Format both inputs with our JSON Formatter first, then paste them here for clean structural comparison.