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Free tool

Chrome extension manifest validator

Paste your manifest.json and catch errors, deprecated Manifest V2 keys, and the exact permission warnings Chrome shows your users — before a rejected store review.

How it works

Paste, read, fix.

  1. 01

    Paste

    Drop in your manifest.json — nothing is uploaded.

  2. 02

    Read the flags

    Errors, warnings, and the exact permission prompts your users see.

  3. 03

    Ship lean

    Fix issues and trim scary permissions before you submit.

FAQ

The manifest, explained.

It flags missing required fields (manifest_version, name, version), Manifest V2 leftovers, host patterns in the wrong place, missing description/icons, and — crucially — the exact install warnings each permission shows your users.

No. Parsing and validation run entirely in your browser — your manifest never leaves your device.

Yes — they use Chrome's exact install-warning strings from the official permissions reference, so you see the real text a user reads before installing.

A scary permission prompt is one of the most common reasons users abandon an install or uninstall soon after. Keep your manifest lean — and when users do leave, UserFeed's uninstall feedback tells you whether permissions were the reason.

Lean manifest shipped? Now learn why users leave.

A lean manifest gets the install. UserFeed tells you what happens next — a branded uninstall feedback form and drop-off funnel, free for one extension.

Explore UserFeed