100% Free Tool

Visual Diff Checker

Detect visual regressions instantly. Compare staging vs production URLs, or upload design mockups vs implementation screenshots.

Note: This may take 10-20 seconds to crawl both URLs.

What is Visual Regression Testing?

Visual Diff Checking finds pixel-perfect differences between two versions of a webpage or image. It is an essential technique for QA engineers and developers to ensure that code changes do not break the UI.

How it works

Our tool overlays the "Before" and "After" images and highlights mismatched pixels in neon pink. If the images are identical, the screen remains clean. Even a 1px shift in a button's position will be detected instantly.

When to use it?

  • Pre-Deployment: Compare your Staging environment against Production.
  • Library Updates: Verify that updating a CSS framework didn't break layout.
  • Responsive Testing: Check layout stability across different screen widths.

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Side-by-Side Comparison

View differences instantly with our smart slider or classic side-by-side view.

Pixel-Perfect Precision

Our advanced image processing highlights every changed pixel in red (anti-aliasing sensitive).

URL & Image Support

Compare live websites by URL, or upload your own local screenshots.