Refresh Rate Test — Check Your Monitor Hz Online
Verify your active display refresh rate, frame presentation interval, and hardware compositor synchronization.
Check Display Refresh Rate
Measures hardware display compositor synchronization and calculates precise Hz cadence.
Observed frame cadence aligns with high-refresh display synchronization.
Understanding Display Refresh Rate (Hz)
Refresh rate, expressed in Hertz (Hz), represents the number of times per second your monitor panel updates its pixels with a new image frame from the graphics buffer. Higher refresh rates shorten the interval between frames, resulting in smoother motion and reduced input latency.
Frame Time Reference Matrix
Formula: 1000 ÷ FPS| Target Frame Rate | Exact Frame Time | Operational Context |
|---|---|---|
| 30 FPS | 33.33 ms | Baseline interactive frame rate |
| 60 FPS | 16.67 ms | Universal desktop & mobile standard |
| 90 FPS | 11.11 ms | Smooth motion threshold |
| 120 FPS | 8.33 ms | Half the frame latency of 60Hz |
| 144 FPS | 6.94 ms | Standard esports monitor target |
| 165 FPS | 6.06 ms | Enhanced motion clarity |
| 240 FPS | 4.17 ms | Near-instantaneous frame delivery |
| 360 FPS | 2.78 ms | Sub-3ms frame rendering pipeline |
This test measures presentation timing as delivered by the browser rendering pipeline and operating system display compositor. It does not replace optical hardware photodiode tools for laboratory calibration.
Frequently Asked Questions
How does an online test measure monitor refresh rate?
Modern web browsers synchronize their animation frame loop (requestAnimationFrame) directly with the operating system display compositor. By timing hundreds of consecutive frame intervals with performance.now(), the test calculates the central tendency Hz frequency of your active display.
Why is my 144Hz or 240Hz monitor showing 60Hz?
Common reasons include: (1) Windows/macOS display settings defaulting to 60Hz, (2) browser hardware acceleration disabled, or (3) connecting via an older HDMI cable that does not support high-bandwidth refresh rates.
Can this test detect Variable Refresh Rate (G-Sync or FreeSync)?
When VRR is active, frame delivery intervals dynamically adjust to rendering load rather than sticking to a rigid frequency, causing wider inter-quartile variance across measured samples.
Is browser-based Hz measurement 100% equivalent to hardware probes?
No. Browser testing measures presentation cadence delivered through the OS compositor. Physical optical measurements require specialized oscilloscope photodiode sensors.
Related Refresh Tools
Browse All 25 Tools →FPS Test
FPSAccurately measure your browser frame rate, average FPS, 1% lows, and instantaneous render stability.
Frame Time Test
msAnalyze frame duration in milliseconds (e.g. 16.6ms for 60Hz, 6.94ms for 144Hz) and frame time variance.
Frame Pacing Test
msDetect frame delivery unevenness, micro-stutters, and presentation queue pacing anomalies.
Frame Skipping Test
BlocksVerify if your monitor overclock or custom resolution is genuinely displaying all frames without dropping cycles.
Ghosting Test
pxAssess pixel response time, trailing artifacts, inverse ghosting (overshoot), and motion smearing.