PerfectPixel by WellDoneCode (pixel perfect)

PerfectPixel adds a semi-transparent image overlay on top of any web page, letting you compare your frontend implementation against the original design mockup directly in the browser. Upload a design comp, adjust opacity, and immediately see where your code diverges from the spec — with pixel-perfect accuracy. No more switching between tabs or squinting at two screens side by side. How it works: install the extension, open any page, and drop in an image — drag and drop, paste a URL, paste from clipboard, or use the file picker. Position and scale the overlay, then adjust opacity to compare. Features: - Overlay any PNG, JPG, or SVG on any web page - Adjustable opacity for real-time visual comparison - 4 blend modes (Difference, Invert, Multiply, Overlay) plus Normal — each useful for catching different types of mismatches - Lock the overlay to click through it and interact with page elements underneath - Mobile designs in DevTools device mode: move PerfectPixel to the browser's side panel, so the viewport stays clear - Per-domain persistence: your layers stay saved per site and restore automatically across browser sessions - Multiple layers per domain - Scaling, repositioning, and centering controls - Keyboard shortcuts for common actions Pro features: - Unlimited simultaneous layers (free tier supports 2) - Folders to group layers - Layer rotation - Dark theme - Custom icon, accent color, and custom CSS Built for frontend developers, QA engineers, agencies, and development teams who need to verify that what they shipped matches what was designed. 350,000+ developers. 10+ years on the Chrome Web Store.