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Text & Code Diff Checker

Compare two text files, code snippets, or markdown documents side-by-side with visual line additions (+), deletions (-), and unified change statistics.

No Watermarks
Zero Server Uploads
Last updated:
+6 additions-7 deletions
Comparison Output
14 lines processed
1-
function calculateTotal(items) {
2-
  let subtotal = 0;
3-
  for (let i = 0; i < items.length; i++) {
4-
    subtotal += items[i].price;
5-
  }
6-
  const tax = subtotal * 0.05;
7-
  return subtotal + tax;
1+
function calculateTotal(items, taxRate = 0.08) {
2+
  // Use modern reduce for array aggregation
3+
  const subtotal = items.reduce((sum, item) => sum + item.price, 0);
4+
  const tax = subtotal * taxRate;
5+
  const discount = subtotal > 100 ? 10 : 0;
6+
  return subtotal + tax - discount;
87
}

Visual Text & Code Comparison

Quickly verify code changes between software versions, proofread document revisions, or review edited clauses in legal contracts.

The diff algorithm computes the Longest Common Subsequence (LCS) entirely in your browser memory, keeping your code and sensitive documents 100% private.

How to Use Text & Code Diff Checker (Step-by-Step)

1

Paste the original text in the left panel and the modified text in the right panel.

2

Select Split (Side-by-Side) or Unified view according to your preference.

3

Review highlighted green additions, red deletions, and inline character modifications.

Applications

Common Use Cases

  • Inspect code changes between two versions before submitting pull requests.
  • Compare legal contract revisions to identify altered clauses.
  • Find subtle punctuation, spacing, or spelling differences between two text drafts.

Privacy Guarantee

Zero Server Uploads

Unlike traditional online converters that upload your confidential documents to external cloud servers, MultiToolX executes computations in your browser runtime via HTML5 Canvas, Web Crypto, and WebAssembly.

Your data never leaves your device and cannot be viewed, stored, or harvested by anyone.

Companion Step-by-Step Guide

Text and Code Diff Comparison: Side-by-Side Visual Change Analysis

A complete guide on comparing text and code revisions. Detect subtle differences, whitespace changes, and code modifications in your browser.

Read Full Guide

FAQ

Frequently Asked Questions

Does the diff checker support syntax highlighting for code?

Yes. It supports code files, JSON, Markdown, and plain text with clear change highlights.

Is there a limit on text length?

Because processing runs on your local JavaScript engine, it can diff thousands of lines smoothly.