All gaming tools
HDR Test
Check if HDR is actually on for your display
Checks the browser's (dynamic-range: high) media feature, where supported. This reflects what the OS/browser report, not a guarantee your panel is currently displaying true HDR.
Browser reports: Unknown / unsupported
SDR reference (clipped at 255)
Illustrative "HDR headroom" patch
A normal web page is capped at standard 8-bit brightness — it cannot actually push extra HDR brightness out of your panel. Confirming real HDR requires enabling HDR in your OS display settings on a genuinely HDR-capable screen.