How to Measure Display Refresh Rate and FPS

When this guide is useful

We will explain the measurement conditions and how to read the values when searching for ``monitor Hz confirmation'', ``refresh rate measurement'', ``FPS/frame dropping test in browser''.

• I want to check whether settings such as 60Hz, 120Hz, 144Hz, 165Hz are reflected.
• I want to check the stability of FPS and frame interval of browser drawing
• I want to check whether the refresh rate has decreased after connecting an external monitor.

Settings to check before measurement

• Refresh rate selected in OS display details settings
• HDMI and DisplayPort standards, resolutions, and cables
• Laptop power saving mode and external display settings
• Browser hardware acceleration

Stable measurement method

1. Stop
2. Start the measurement and wait a few seconds to see if the initial shaking has subsided.
3. Additional information: FPS Hz
4. Compare results in window view, full screen view, and separate displays.

Meaning of measurements

This tool measures the interval between calls to requestAnimationFrame. The panel is not directly measured with a meter and is affected by browser load, background limitations, and variable refresh rates.

Please use it as a guide to see if it is stable near 60Hz, 120Hz, 144Hz, etc.

Specific example: When a 144Hz monitor becomes around 60Hz

Check that 144Hz is selected in the OS's display settings and move the test page to the target monitor. Also check the power saving settings and the compatible bands of the cable/conversion adapter.

While measuring, bring the tab to the front and stop video playback or heavy apps. Rather than looking at short-term values, we look at the average over a few seconds and the variation in frame intervals.

1. Check your OS and monitor refresh rate settings.
2. Move the measurement page to the target display and bring it to the front.
3. Measure for a few seconds to see estimated Hz, FPS, and frame time.
4. If the value differs from the expected value, isolate the cable, GPU settings, power saving, and browser load.

This is an estimated value using the browser's requestAnimationFrame, and does not directly measure the physical movement of the panel with a measuring device.

Frequently asked questions

Is it abnormal that the measured value is around 143 even though it is set to 144Hz?

It will vary slightly depending on timer accuracy and variable refresh rate. Please judge based on average value, stability, and OS settings.

Are FPS and Hz the same?

FPS is the number of frames drawn, Hz is the number of display updates. Although related, they may not match depending on app load or synchronization method.