Overview
Percy, acquired by BrowserStack, is the industry-standard visual regression testing platform that automates the process of identifying UI changes across web and mobile applications. Unlike traditional pixel-by-pixel comparison tools, Percy utilizes a sophisticated DOM-snapshotting architecture. It captures the DOM and CSS assets of a page, then reconstructs and renders those assets in its own controlled cloud environment across multiple browsers and screen resolutions. This methodology eliminates 'flakiness' caused by local font rendering or GPU variations. In the 2026 landscape, Percy has integrated AI-powered 'Smart Diffing' which distinguishes between intentional design changes and layout breakage, significantly reducing manual review time. Its positioning is focused on the 'Shift-Left' testing movement, allowing developers to catch UI bugs at the Pull Request level before they reach production. The platform scales from individual developers to global enterprises, providing a centralized hub for designers, developers, and QA engineers to collaborate on visual quality through integrated workflows with GitHub, GitLab, and Bitbucket.