HDR Capability Check

Check the browser HDR capability signal, verify your display setup, and optionally inspect SDR comparison patterns.

Go to test controls

This check runs directly on this page without requiring fullscreen. Review what this browser test can and cannot measure.

Before you start

  • Move the browser to the display you want to inspect.
  • Record the OS HDR setting and room lighting; leave the highlight observation unassessed if you cannot compare the SDR steps.
Step-by-step instructions

How to run this check

  1. Check the browser-reported HDR capability signal shown on the page
  2. Select the same target display in your operating-system settings and confirm its intended HDR mode
  3. Use supported HDR content or calibration and OS/display status to check actual HDR output separately
  4. Optionally choose View SDR comparison patterns and cycle through the ordinary sRGB patterns
  5. Save the actual highlight-step observation or not assessed, OS setting, viewed patterns, and setup; pattern count does not determine a successful result

Check the current browser and display

Checking browser/output HDR capability signal…

  1. Move this browser window to the display you want to check. Select that same display in your operating-system settings and confirm the intended HDR mode and the display's input settings. On Windows, follow Microsoft's HDR settings instructions.
  2. If high dynamic range is not reported, recheck the selected display, OS mode, and browser support, then return to this signal after any change. If it is reported, the browser has exposed a capability; the media query does not confirm active HDR.
  3. To check actual HDR playback, use identified HDR content in a supported video app or game, or a supported calibration tool such as Windows HDR Calibration for Windows 11. Check the OS and display's current output status while it runs, following the product documentation.

SDR comparison patterns

These patterns use ordinary sRGB colors, even when OS HDR is enabled. Compare visible steps, color shifts, or halos under a fixed setup; they do not generate HDR content or measure HDR performance.

Use the arrow controls to change SDR patterns. Press ESC to finish and record your observation.

Illustrated appearances to describe

These are deliberately drawn sRGB illustrations, not photographs or measurements of different panels. Describe the appearance you observe; these samples cannot identify HDR, panel bit depth, color gamut, or backlight technology.

🌟 Light code values

White sample
RGB 255, 255, 255
Gray sample
RGB 204, 204, 204

🎨 Color appearance

Saturated sample
Vivid saturated colors
Desaturated sample
Muted colors

📊 Gradient

Continuous gradient
Smooth gradient
Eight drawn bands
Visible bands

🌑 Bright shapes on dark

Black background
Pure black background
Gray and halo illustration
Gray background with halo

💫 Blooming

Sharp dot illustration
Sharp star
Glow illustration
Blurred glow

Three HDR questions that need different evidence

Layer This page can show Confirm elsewhere
Browser signal dynamic-range and color-gamut media-query matches Browser and operating-system support documentation
Current output Visible differences in SDR patterns under the current display mode Supported HDR content or calibration, plus operating-system, GPU, and display status
Physical performance Nothing numeric Metered nits, gamut, EOTF, and local-dimming tests

What this browser test can tell you

Can help you check

  • Browser-reported dynamic-range and color-gamut capability signals, plus visible differences between SDR comparison patterns.

Cannot measure

  • This test cannot confirm active HDR state, peak nits, gamut coverage, local dimming, or HDR certification.

Interpret this observation

  • The canvas draws ordinary sRGB colors. Record distinct steps, color shifts, or halos as SDR observations, including when OS HDR is enabled.
  • The saved highlight observation follows your selected finding, not the number of patterns viewed. Unassessed steps stay unassessed; setup, OS setting, and actual viewed patterns remain in the notes.
  • A high dynamic-range media-query match is a browser/output capability signal, not proof that HDR is active; operating-system HDR mode, browser support, tone mapping, and color management can all change the result.
  • Check actual HDR output with supported HDR content or calibration and the current OS/display status. These SDR patterns cannot replace that check.
  • Exact brightness and gamut measurements require a calibrated colorimeter or spectroradiometer.
Setup and sources

Recommended setup

  1. Move the browser to the target display and select that display in your operating-system settings.
  2. Confirm the intended OS HDR mode and display input settings; compare SDR patterns with the same display mode and room lighting.

Sources

Methodology reviewed: