How to check your monitor's refresh rate
Use your operating system's display settings to check the configured rate. A browser test answers a different question: which animation cadence is reaching this page right now. Record both when investigating a mismatch.
Windows 11: select the display first
The Advanced display page reports information for the selected display. With several monitors, confirm which one is selected before reading or changing a rate.
- Open Settings → System → Display → Advanced display.
- Select the monitor you want to check and read its reported refresh rate.
- If changing it, use Choose a refresh rate and select a supported option. Available rates depend on the display and connection.
Reference: Microsoft's refresh-rate instructions
macOS: inspect Displays settings
Open Apple menu → System Settings → Displays and select the display. Look for Refresh Rate when that option is available. Options depend on the Mac, connected display, and mode; compatible configurations may offer an adaptive rate rather than one fixed number.
Compare with the browser, on the same monitor
Move the entire browser window onto the selected display, let it settle, and start a fresh Refresh Rate Test. Keep the tab visible and the window focused until sampling finishes. Compare the estimate, confidence, and configured setting; do not replace the OS reading with a rounded browser class.
- Record the configured rate and whether a dynamic/adaptive mode is selected.
- Run the test once with the window settled on that display.
- If the values differ, repeat under comparable power/load conditions and inspect sample details.
When a rate is missing or the estimate is lower
Check the display manual for supported combinations of resolution, rate, cable, port, and adapter. A specification for one mode does not guarantee it through every dock or connection. Do not force an unsupported setting. A lower browser estimate alone does not prove a bad cable or panel: scheduling, power settings, workload, and variable refresh behavior can also explain it. Menu names may differ by OS version.