Display Tests refresh rate Hz requestAnimationFrame

Refresh Rate Test

Estimate display refresh from animation timing in the browser. Not a lab Hz measurement.

Interactive tool

Run the test

Runs in your browser

Estimates Hz from animation timing in this tab — not a lab measurement. Fullscreen often helps. No special permission is required. Compare with your OS display refresh setting.

Permission status

Checked in your browser. DeviceHub does not store permission grants.

  • Special permission Not required

Live results

Metrics update as you run the test. Nothing is uploaded.

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Device information

Labels and capability details reported by your browser.

No device details yet.

Description

About Refresh Rate Test

Introduction

This page estimates refresh rate from animation-frame timing in the browser. It is not a laboratory Hz meter. Power saving, browser scheduling, and windowed mode can change the result.

What this tool does

It samples frame timestamps and reports an estimated Hz. It does not read the panel’s EDID directly.

When to use it

Use it for a quick browser-context estimate. Confirm the mode in your OS display settings when accuracy matters.

How it works

Supported: all modern browsers that run animation frames. Limits: estimates can sit below the panel’s rated Hz under load or without fullscreen. Permissions: none (fullscreen optional). Hardware: any display; high-Hz panels need a matching OS mode. Expected: an approximate Hz number close to 60/120/144 in good conditions, with variance.

Step-by-step instructions

  1. Optionally enter fullscreen.
  2. Run the estimate and wait for it to settle.
  3. Compare with the refresh rate selected in your OS.

Common problems

Lower than expected Hz often means the browser is not matching the panel mode, or the tab is under load.

Privacy explanation

Timing stays local. No permission beyond optional fullscreen.

Runtime principles

Built for the browser

What happens when you run this test — without downloads or accounts.

  1. 01

    Runs in your browser

    Refresh Rate Test uses standard web APIs — no install, extension, or desktop app required.

  2. 02

    Reads what the browser allows

    Results come from events and capability signals the web platform exposes for this session.

  3. 03

    Private by default

    Input and diagnostic values stay in your browser session for display — nothing is sold as media.

Compatibility

Supported browsers

Expected support for modern engines. Individual APIs may still vary by device.

  • Chrome

    supported

    Latest stable

  • Firefox

    supported

    Latest stable

  • Safari

    supported

    Latest stable

  • Edge

    supported

    Latest stable

Devices

Supported devices

Hardware and form factors this browser test is designed to exercise.

  • Laptop & desktop displays

    CSS pixels, DPR, and color-capable screens.

  • External monitors

    When the browser window is on that display.

  • Mobile screens

    Phone and tablet viewports for layout checks.

Privacy

Your data stays with you

Refresh Rate Test is built privacy-first. Diagnostics run in your browser session whenever web APIs allow.

Read our privacy policy

Troubleshooting

Common problems

Quick fixes before you dig into FAQs.

Reported Hz is far below my monitor setting
Confirm the OS refreshed the display to the target rate, use a focused fullscreen tab, close heavy CPU loads, and remember this is a rAF-based estimate, not a hardware timing analyzer.
Numbers jump between 60 and 120
VRR, battery savers, background throttling, and multi-monitor focus can change frame cadence. Retest with the window on the target display and power profiles set to performance.
Laptop lid closed / external only looks wrong
Move the browser window onto the external monitor, fullscreen there, and disable mirrored mixed refresh setups when possible.

FAQ

Frequently asked questions

Structured answers for users and FAQ rich results.

Browse FAQs
Is this my exact monitor Hz?
It is an estimate from browser timing, not a lab instrument reading.
What do browsers expose?
Animation-frame timestamps you can turn into an estimate.
What do they not expose?
Direct access to the panel’s certified refresh programming.
Which browsers work?
Chrome, Edge, Firefox, and Safari can all estimate; results vary with load and mode.
Permissions or hardware?
No special permission. Fullscreen helps. Use the display mode you care about.
What should I expect?
A nearby Hz estimate (for example ~60 or ~120) that can move between runs.

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Updates coming soon

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Release notes

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