Pixel Perfect Advanced Autor: Aygul

Line up your build with the design, down to the pixel.

Pixel Perfect Advanced overlays your design mockup directly on top of any live web page, so you can compare your implementation against the source and fix every difference. Load a screenshot or an export, drop it over your page, dial the opacity, and see exactly what is off.

Built for frontend developers and designers who care about getting the details right.

WHAT IT DOES
Overlay one or more design images on any page, then adjust opacity, position, scale and blend mode until your build matches. Lock an overlay to click straight through it to the page underneath. Everything you set is remembered per site, so your overlay is waiting for you the next time you open that page.

OVERLAYS AND COMPARISON
- Unlimited overlay layers on any page
- Five blend modes: normal, invert, difference, multiply and overlay (difference makes every mismatch obvious)
- Per-layer opacity, scale and pixel-precise X and Y positioning
- Keyboard nudging with configurable small and large steps
- Click through locked overlays so the page stays usable
- Fixed or absolute positioning for long, scrolling pages
- Fit-to-width, center and snap-to-edge alignment helpers
- Window-to-layer viewport emulation to match a mockup width without resizing your browser

PANELS AND INPUT
- Two panel modes: a docked side panel and a draggable floating panel that collapses to a compact pill
- Add images by upload, URL, paste (Ctrl or Cmd + V) or drag and drop anywhere on the page
- Undo and redo for layer changes

LIBRARY AND PRESETS
- A built-in media library that keeps every imported image, with folders and pinning
- Reusable presets for your opacity and blend defaults
- Per-site auto-restore: layers, opacity and position come back exactly as you left them

WHY YOU WILL WANT IT
Eyeballing a design against a browser never catches everything. Overlaying the real design on the real page does. Difference mode turns a spacing that is two pixels off, or a color that is slightly wrong, into something you can see at a glance, so review takes minutes instead of a back and forth with the designer.

PRIVATE BY DEFAULT
No account. No sign-in. No analytics or telemetry. Your images and settings stay in your own browser and are never sent anywhere. The extension only draws on the page you are looking at and remembers your setup locally.

Works on Chrome, Edge and Firefox. Light, dark and system themes. Available in English and Russian. Free.