The best pixel perfect and design QA extensions for Chrome (2026)

7 min read · Updated November 2026 · By the makers of Tracepaper

We make Tracepaper, so weigh this page with that in mind. Every other tool here is one we'd recommend for the job named next to it. User counts and ratings are from the Chrome Web Store (our scan of every listing, October 2026); prices are from each vendor's own page, checked in November 2026. Something out of date? Email support@decisionscalc.com and we'll fix it.

Checking a build against its design usually takes a handful of extensions: one to overlay the design, one to measure, a colour picker, a font finder and a window resizer. Here's the best tool for each job, and the all-in-one option we make.

At a glance

Quick picks

• You want one toolbar for the whole design check: Tracepaper.
• You want to move and edit things on the page while you check: VisBug.
• You only need a colour picker: ColorZilla. Only fonts: WhatFont.
• You need to copy an element's CSS: CSS Peeper (free) or Tracepaper Pro (also copies Tailwind classes).

1. Tracepaper (ours)

We built Tracepaper to replace the five or six extensions below with one toolbar. Free, with no limits: overlay your Figma or image export with unlimited layers and difference mode, measure sizes and gaps, snapping guides, exact screen sizes, a colour picker with a magnifier (HEX, RGB, HSL, OKLCH) and a font finder that shows the font actually rendered. Pro ($4.99/month, $39/year or $79 once) adds a CSS inspector with Copy CSS and Copy as Tailwind, WCAG contrast checks and a page audit. It runs only when you click it.

Not the pick if you want to drag and edit elements on the page (try VisBug).

2. PerfectPixel

The best-known overlay extension: put a design image over the page, set its opacity and nudge it into place. Its free plan now allows 2 layers per site and shows ads in its panel (per its listing); more layers need Pro. Store reviews from 2026 complain about the new limit.

See Tracepaper vs PerfectPixel.

3. VisBug

Google's free, open-source design tool, great for poking at a live page: inspect styles, see the spacing between elements, and move, resize or edit things in place to try a fix. It doesn't overlay a design image.

4. CSS Peeper

Click an element to see its styles, colours and assets in a tidy panel, and copy them. Some recent reviews mention donation pop-ups. See Tracepaper vs CSS Peeper.

5. ColorZilla

The classic eyedropper, with about 4 million users: pick any colour on the page, keep a history and build gradients.

6. WhatFont

Hover any text to see its font, size and colour. Simple and free.

7. Window Resizer

Resize the browser window to preset sizes to test breakpoints. The window size isn't quite the viewport your CSS sees (scrollbars and browser chrome take space); Tracepaper's Screen sizes sets the viewport itself.

8. Page Ruler

Draw a box on the page to see its size and position. Basic, but quick.

Questions

What is the best pixel perfect extension for Chrome?

For overlays: Tracepaper (unlimited free layers and difference mode) or PerfectPixel (2 free layers per site). For checking and editing a live page: VisBug.

Is there a free PerfectPixel alternative?

Yes. Tracepaper overlays designs with unlimited layers free, plus measuring, guides, a colour picker and a font finder.

How do I overlay a Figma design on a website?

Export the frame as PNG at 1x, make the viewport exactly as wide as the frame, then overlay it at about 50% opacity. Full steps: how to overlay a Figma design.