A browser result near 60 FPS can have several causes. The selected display mode may be 60 Hz, the browser may be scheduling at a lower rate, or the sample may have been interrupted. Compare one setting at a time to narrow the cause.
1. Confirm the selected display and its active mode
In Windows, open Settings → System → Display → Advanced display. Select the display you are checking and inspect its current refresh rate. Microsoft’s refresh-rate guide explains the available choices, including modes that also change resolution.
On a Mac, open System Settings → Displays and select the relevant display. Available options depend on the Mac and display. Apple’s display settings guide explains the refresh-rate control and adaptive options. An adaptive mode can vary its refresh rate during use.
2. Make a clean browser comparison
Keep the window entirely on the display being checked. Leave the tab visible, turn this page’s animation load off and pause demanding background work. Run the same 10- or 20-second test again. Compare a completed run with another completed run, rather than an initial live number.
If the discrepancy remains, repeat in another current browser. This narrows the question: a change between browsers suggests a browser or compositor condition worth investigating. Record the browser and setting that changed the reading.
3. Check power-saving and mobile settings
On a notebook, compare the relevant power mode and whether it is running on battery or external power. Change one condition at a time and record it. For ProMotion devices, Apple’s guides for iPhone and iPad document a display refresh limit of 60 Hz in Low Power Mode. A phone advertised as 120 Hz can therefore produce a lower reading under a supported power-saving condition.
4. Simplify a multiple-display setup
Different displays, the selected primary display and the desktop compositor can complicate browser timing. As a comparison, try the tested screen as the only active display or make it primary, then repeat. The TestUFO browser checklist includes multiple-monitor and power considerations.
If the result changes, note exactly what changed and restore your preferred display arrangement afterward.
5. Follow the connection from port to monitor
Write down the target as a pair, such as 2560 × 1440 at 144 Hz, then check it along the whole path. Keep HDR, color-depth options and the number of connected displays in the notes because available combinations can differ.
| Check in order | What to confirm |
|---|---|
| Computer port | Read the computer’s specification for that exact output. For USB-C, confirm that the port supports the required display connection. |
| Cable or adapter | Check its specified resolution and refresh support. If available, compare a known compatible cable without changing other settings. |
| Dock | Check the dock’s display table for your computer, chosen outputs and number of screens. Compare a direct connection when the computer and monitor support it. |
| Monitor input | Use the manual’s supported timing table for the connected input and resolution. Check any input-mode setting the manual requires. |
After each change, return to the operating system’s display settings and confirm the active resolution and refresh rate again. If the higher rate appears only at a lower resolution, record both combinations. Use the specifications for each part of the connection to confirm supported modes.
Microsoft’s Surface display guidance illustrates how the device, connection and dock affect available modes. Use the equivalent documentation for your hardware before buying replacements.
Compare your selected refresh rate with browser FPS
In the FPS tool, optionally enter the refresh rate selected in your operating system. Leave it unknown if you have not checked. The entered rate is a reference for the advice shown beside your measured result. Change the display mode in your system settings.
When the readings still disagree
Keep the browser result alongside the system’s active mode and the monitor’s own information screen, if it provides one. State the browser, test duration, load and display arrangement when seeking help. A repeatable mismatch gives support a specific behavior to investigate.
Review what FPS and Hz each describe, or inspect exactly how this test samples time.
Platform instructions and source links checked 25 October 2026. Menu wording and browser behavior can change.
The screen information readout helps distinguish window size, CSS pixels and DPR. Use it to record the browser context alongside your FPS report.