DarkCheck

Convert any site to dark mode instantly. Audit text contrast against WCAG AA/AAA with one-click colour fix suggestions.

Not every website supports dark mode. DarkCheck fixes that — for everyone. Whether you are a regular user who prefers browsing in dark mode, or a developer building the next great web experience, DarkCheck gives you something no other extension does: a real, simulated dark mode on any website you visit, plus a full audit of everything that looks broken under it. For the General Public — Dark Mode on Every Website, Instantly If you spend most of your time in dark mode, you already know the frustration. You open a website and get blasted with a bright white page because the site never bothered to support dark mode. DarkCheck solves this immediately. Click the extension, hit Simulate and DarkCheck wraps any website in a dark mode environment in real time — no waiting for the developer to add support, no workarounds, no browser flags. Any site, any time, instant dark mode. Your eyes will thank you. DarkCheck is designed to be simple enough for anyone to use. You do not need to know anything about code, design, or accessibility. Open a website, click one button, and it just works. For Developers and Designers — A Full Dark Mode Audit If you are building websites, DarkCheck goes much deeper. Its simulation engine doesn't just make the page look dark — it actively tests every element on the page under those dark conditions against WCAG AA accessibility standards (the global benchmark for readable contrast). You get exact contrast ratio scores, a results panel listing every failing element, one-click highlights that point to failures directly on the live page, and a suggested corrected hex color for every single issue found. No other tool gives you this in one place, in real time, without leaving the browser. This matters because a color that looks perfectly readable in light mode can completely fail in dark mode. Standard contrast checkers don't account for this. DarkCheck does. The Simulation Engine — How It Works When you activate DarkCheck, it injects a live dark mode layer directly onto the page — transforming backgrounds, surfaces, and elements in real time so what you see is exactly what a dark mode user experiences. For general users this means an instant, comfortable dark mode on any site. For developers and designers it means every contrast score and audit result is grounded in real dark conditions, not a theoretical estimate. Key Features — Instant dark mode simulation on any website with one click, for any user — No account, no signup, no data collection — fully local and private — Full WCAG AA contrast audit run under real simulated dark conditions — Exact contrast ratio scores for every element on the page — One-click element highlighting to locate failures directly on the live page — Suggested hex color fixes for every failing element — Clean summary panel showing total elements scanned, passing, and failing — Built for everyone — from everyday users to professional developers Who It Is For DarkCheck is for anyone who prefers dark mode and is tired of websites that don't support it. It is for developers who want to ship accessible dark mode experiences with confidence. It is for designers who need to validate color decisions under real dark conditions. It is for QA testers who want a fast accessibility gut-check without switching tools. And it is for accessibility advocates who want a simple way to audit any site they encounter. If you live in dark mode, DarkCheck is the extension you have been waiting for. If you build for the web, it is the audit tool that finally accounts for dark mode the right way. Every website deserves dark mode. Now every website has it.