Text & Code Diff

Text & Code Diff Checker

Compare two pieces of text or code to instantly spot additions, deletions, and modifications. Runs 100% locally in your browser to protect sensitive keys and proprietary source code.

Pure client-side LCS diffing, zero server transmission

100% Client-side · Zero Server Upload

Text & Code Diff Checker

Presets:

Original Text / Before

function fetchUserData(userId) {
  const url = "/api/user/" + userId;
  return fetch(url)
    .then(res => res.json())
    .then(data => {
      console.log("Loaded", data);
      return data;
    });
}

Modified Text / After

async function fetchUserData(userId: string): Promise<UserData> {
  const url = `/api/v2/users/${encodeURIComponent(userId)}`;
  const res = await fetch(url, { cache: "no-store" });
  if (!res.ok) {
    throw new Error(`Failed to load user: ${res.status}`);
  }
  const data = await res.json();
  return data;
}

Ignore whitespaceIgnore case

+8 added, -8 removed, 1 unchanged

1function fetchUserData(userId) {
const url = "/api/user/" + userId;
return fetch(url)
  .then(res => res.json())
  .then(data => {
    console.log("Loaded", data);
    return data;
  });
9}
1async function fetchUserData(userId: string): Promise<UserData> {
const url = `/api/v2/users/${encodeURIComponent(userId)}`;
const res = await fetch(url, { cache: "no-store" });
if (!res.ok) {
  throw new Error(`Failed to load user: ${res.status}`);
}
const data = await res.json();
return data;
9}

How it works

Client-side LCS diff engine designed for privacy

Many online diff tools upload your snippets to a remote server. For sensitive configs, API tokens, passwords, or intellectual property, this creates major security and compliance risks.

Dev Desk Diff runs an in-memory Longest Common Subsequence (LCS) algorithm directly in your browser's JavaScript engine. No payload ever leaves your device.

LCS dynamic programming algorithm detects added, removed, and unchanged lines offline.

FAQ

Text & Code Diff Checker · FAQ

Is my code or text uploaded to any server?

Never. All diff computation occurs strictly inside your browser memory. You can disconnect your network and it will continue to work seamlessly.

Does it support side-by-side split view?

Yes. You can switch between Split (side-by-side) and Unified (inline) views with a single click.

Can I export the diff as a patch?

Yes. Click 'Copy Unified Diff' to copy a standard git-style patch to your clipboard.

Text & Code Diff Checker

Text & Code Diff Checker

Client-side LCS diff engine designed for privacy

Text & Code Diff Checker · FAQ

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