Refresh Rate Test

Measure the exact number of times your display updates per second (Hz). Perfect for verifying 120Hz, 144Hz, or 240Hz panels.

Important: Ensure battery saver is off, hardware acceleration is on, and keep this tab in focus.
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How Refresh Rate Testing Works

The refresh rate of a display, measured in Hertz (Hz), indicates how many times per second the screen draws a new image. A standard 60Hz display updates 60 times a second, while a modern 144Hz or 240Hz monitor updates significantly faster, providing a buttery-smooth experience in competitive gaming and daily scrolling.

This diagnostic tool utilizes your browser's native hardware-accelerated rendering engine (requestAnimationFrame). By measuring the precise microsecond gap between consecutive screen paints, we calculate your actual real-time display frequency. Once you verify your panel is running at its maximum speed, you may also want to check it for hardware defects using our free Dead Pixel Test.

Testing 120Hz, 144Hz & 240Hz Displays (Apple, Samsung, Asus)

Not all devices handle high refresh rates the same way. Here is what you should know based on your brand:

Apple (iPhone ProMotion & iPad Pro): Apple devices with ProMotion technology dynamically adjust their refresh rate up to 120Hz. However, Safari will often limit web animations to 60Hz if your phone is in "Low Power Mode" to preserve battery life. Make sure it is disabled before running the test.

Samsung Galaxy & Android Flagships: Most modern Android phones feature 90Hz or 120Hz AMOLED screens. Similar to Apple, Android's "Battery Saver" will lock your display to 60Hz. Disable it to verify your screen's true capabilities.

Gaming Monitors (Asus, Alienware, LG, BenQ): If you just bought a 144Hz, 240Hz, or even 360Hz gaming monitor, it will likely run at 60Hz out of the box! You must manually open Windows Display Settings or your NVIDIA/AMD control panel to unlock the higher refresh rates. Additionally, make sure you are using a DisplayPort cable, as older HDMI versions do not have the bandwidth for high Hz gaming.

Troubleshooting & FAQ

My phone is 120Hz, but the test shows 60Hz. Why?

This is almost always caused by software limitations. If your iPhone or Samsung Galaxy is in "Battery Saver" or "Low Power Mode", the OS automatically restricts the browser to 60Hz to save battery. Disable battery saver to test the true 120Hz speed.

Why is my 144Hz or 240Hz gaming monitor showing 60Hz?

Check your operating system settings. In Windows, go to Display Settings > Advanced Display and ensure the refresh rate is actually set to 144Hz or 240Hz. Monitors often default to 60Hz out of the box. Also, ensure you are using a DisplayPort cable, as older HDMI versions cannot handle high refresh rates.

Does this Hz test work on iPhone, iPad, and Android?

Yes! This test works universally across Apple devices (including iPad Pro and iPhone ProMotion displays), Samsung devices, and all Android smartphones, directly through your web browser.

Why does the number fluctuate slightly (e.g., 143.8Hz)?

This is perfectly normal. Web browsers are not real-time operating systems; background tasks, CPU interrupts, and V-Sync polling can cause microsecond variations in rendering time. A result of 143.8Hz or 144.1Hz is structurally a perfect 144Hz display.