Monitor Refresh Rate Tester

How this tester works

Browsers schedule animation callbacks once per display refresh. The tester registers a requestAnimationFrame callback, counts how many fire over a 4-second window, divides by elapsed time, and rounds to the nearest standard refresh rate. Modern browsers cap rAF at the actual display rate; the result tells you what the operating system has negotiated with your monitor in this browser tab right now.

Standard refresh rates and what they mean

• 60 Hz: the long-time office and TV standard. Smooth enough for documents, email, and most video. Default for any monitor that does not advertise a higher rate.
• 75 Hz: common on budget gaming monitors and 1440p productivity panels. A noticeable upgrade over 60 Hz for scrolling and mouse motion.
• 90 to 120 Hz: the modern phone and mid-range gaming sweet spot. iPad ProMotion runs 120 Hz, recent iPhones run 90 to 120 Hz, and most $300 to $500 gaming monitors hit 144 Hz.
• 144 to 165 Hz: mainstream gaming. Significantly smoother than 60 Hz; the upgrade most office workers do not need but every esports player wants.
• 240 Hz and above: competitive gaming territory. The visible difference from 144 Hz is real but subtle and only matters in fast-twitch first-person shooters.

Tips for accurate measurement

• Keep this tab in focus. All major browsers throttle backgrounded or hidden tabs to 30 Hz to save battery. The tester reports throttled rates as 30 Hz; bring the tab forward and re-run.
• Close power-saver mode. Windows battery saver and macOS Low Power Mode reduce screen refresh on supported displays. Plug in the laptop or disable the mode for an accurate reading.
• Use the right cable. HDMI 1.4 caps at 60 Hz at 1080p and 30 Hz at 4K. DisplayPort 1.2+ or HDMI 2.0+ are required for 120 Hz at 4K. Many gaming monitors ship with both ports; verify which one you are using.
• Set the refresh rate in OS display settings. Windows and macOS sometimes default to 60 Hz on a high-refresh display. Right-click desktop > Display Settings > Advanced > Refresh Rate (Windows) or System Settings > Displays > Refresh Rate (macOS).
• Multi-monitor users: drag this browser window onto each monitor and re-test. The browser reports the refresh rate of whichever display the window is on.

Common reasons your monitor is not running at advertised speed

• Cable bandwidth limit. A 144 Hz monitor connected via HDMI 1.4 caps at 60 Hz. Switch to DisplayPort or HDMI 2.0+.
• OS display setting. Windows and macOS often default new displays to 60 Hz; manually pick the higher rate in display settings.
• GPU driver out of date. Older drivers may not advertise the full refresh-rate menu. Update via NVIDIA / AMD / Intel control panels.
• Variable refresh rate (VRR / G-Sync / FreeSync) negotiating low. If the GPU is rendering 30 FPS, a VRR display will refresh at 30 Hz to match. Test with a fast-moving page or a high-FPS source to see the panel's max.
• Daisy-chained or hub monitors. USB-C hubs and some KVMs cap bandwidth to 60 Hz even if the underlying monitor supports more.
• Browser tab throttling. Inactive tabs run at 30 Hz. Pin the tab and bring it to focus before testing.

What the moving box shows you

The animated bar travels left to right at one cycle per second on a track ruled at 60 Hz baseline. On a 60 Hz display the bar appears as visible discrete steps; on 120 Hz it is twice as smooth; on 240 Hz it appears continuous. The visual is a sanity check on the numeric reading: if the tester says 144 Hz but the bar visibly steps at 60 Hz cadence, the OS is probably running a 60 Hz driver mode despite advertising the higher rate.

FAQ

What is a monitor refresh rate?

Refresh rate is how many times per second your monitor redraws the entire screen, measured in hertz (Hz). 60 Hz means 60 redraws per second, the long-time desktop standard. Higher refresh rates make motion look smoother. Common values: 60 Hz (office monitors and TVs), 75 Hz (low-end gaming), 90 to 120 Hz (mid-range gaming and modern phones), 144 to 165 Hz (mainstream gaming), 240 Hz (high-end competitive gaming).

How does this tester work?

The tester uses the browser's requestAnimationFrame callback, which fires once per display refresh. By counting callbacks over a 3 to 5 second window, the tester computes the average frames per second, which equals your monitor's effective refresh rate. The result is bucketed to the nearest standard Hz value to filter normal jitter (typically plus or minus 2 to 3 Hz on a steady display).

Why is my refresh rate showing as 60 Hz when my monitor is 144 Hz?

Three common causes. First, the display cable: HDMI 1.4 caps at 60 Hz at 1080p resolution, you need DisplayPort or HDMI 2.0+ for higher rates. Second, the OS setting: Windows and macOS default new displays to 60 Hz; manually set the refresh rate in Display Settings (Windows) or System Settings > Displays > Refresh Rate (macOS). Third, the browser tab being inactive or backgrounded throttles requestAnimationFrame to 30 Hz. Bring this page to focus and try again.

Does refresh rate equal frame rate (FPS)?

Related but not the same. Refresh rate is the monitor's hardware capability (60, 144, 240 Hz). Frame rate (FPS) is how many frames per second the GPU is actually rendering. A 144 Hz monitor displaying a game running at 60 FPS still shows 60 FPS, the extra refresh slots show duplicate frames. Smooth motion requires both: a high-refresh display and software (game, browser, video player) able to keep up.

Will a higher refresh rate make my work computer faster?

Not for productivity tasks like spreadsheets, code, or email. Higher refresh rates make scrolling, mouse movement, and animation noticeably smoother and reduce eye strain over long sessions. The improvement is most noticeable in gaming, video editing, and CAD work. For pure office work, 60 Hz is fine; 90 to 120 Hz is a quality-of-life upgrade. The visual difference between 60 Hz and 144 Hz is obvious; between 144 Hz and 240 Hz it is subtle and only matters in fast-twitch gaming.