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Display Tech7 min read

What Is HDR on Monitors? Peak Brightness, Color Gamuts, and Bit Depth

What distinguishes real HDR (Mini-LED, OLED, 1000 nits) from fake entry-level HDR400 on standard edge-lit SDR monitors.

Published: 2026-03-10Reviewed: 2026-08-30
Interactive Diagnostic Tool
HDR Test

Detect HDR display support, wide color gamut headroom, and peak luminance metadata.

Launch

1.The Three Pillars of True HDR

Real HDR requires three hardware capabilities: peak luminance exceeding 600–1000 nits, true 10-bit color depth (1.07 billion colors) with wide DCI-P3 gamut coverage, and localized full-array dimming (FALD) or self-emissive OLED pixels to maintain deep black levels simultaneously.

2.Why Entry-Level HDR400 Looks Washed Out

Standard edge-lit LCD monitors rated for VESA DisplayHDR 400 lack local dimming. When HDR is enabled, the entire edge backlight is forced to 100% brightness, washing out blacks into milky gray and reducing actual contrast.

Frequently Asked Questions

How do I test if my browser and display support HDR?

Use the FPSRate HDR Test to query your browser CSS dynamic-range media capabilities and inspect peak luminance test ramps.