Audit Any Website
in Seconds

SiteTester runs 62 individual checks across 6 categories: SEO (12 checks), Performance (12), Accessibility (10), Design & Structure (8), Aesthetics (8), and Security (12). Each check produces a score from 0-100, and the overall grade is a weighted average.

No — SiteTester's scores are heuristics. It fetches your page's server HTML and response headers and reasons about them (meta tags, headings, header presence, CSS patterns, resource counts, and so on). It does not run Google Lighthouse, an axe-core accessibility audit, or a real headless browser, so it can't measure runtime metrics like Core Web Vitals (LCP/CLS), execute JavaScript, or catch issues that only appear after render. Treat the grade as a fast, directional signal and a prioritized to-do list — not a certification. Security-header and metadata checks are largely definitive; performance and accessibility checks are best-effort approximations.

Yes, SiteTester is completely free to use. There are no limits on the number of sites you can test. We sustain the tool through non-intrusive advertising.

SiteTester analyzes the initial HTML response from the server. Sites that rely heavily on client-side JavaScript rendering (React, Vue, Angular SPAs) may show lower scores because the content visible to users is not present in the initial HTML. We clearly flag this limitation in results.

Scores are based on established web development best practices and standards. While no automated tool can replace a full manual audit, SiteTester provides a reliable overview of a site's technical health. Color contrast checks are heuristic-based rather than pixel-level WCAG computation.

Scan results are stored only in your browser's local storage for your convenience. We do not store your scan results on any server. Your scan history stays on your device and can be cleared at any time.

SiteTester works in all modern browsers including Chrome, Firefox, Safari, and Edge. We recommend using the latest version for the best experience.