Refresh Rate Tester
Detect your display's true refresh rate in hertz. The test watches your browser's animation clock for a few seconds, then reports the rate it locked onto and how steady it was — keep this tab in focus while it measures.
Collecting frames…
How it works
The browser fires requestAnimationFrame once per display refresh, so the gap between callbacks mirrors how often your monitor redraws. We record those gaps for a few seconds and take the median— using the middle value rather than the average keeps the odd slow frame (from garbage collection or background work) from skewing the result. Inverting that median gives the refresh rate, which we snap to the nearest standard if it's within a few percent. The histogram shows the spread of frame intervals: a tall, narrow spike means a rock-steady display.
Common refresh rates
60 Hz is standard for most laptops and office monitors. 120, 144, and 165 Hz are common on gaming displays, with 240 Hz and aboveon high-end esports panels. Phones often run 90 or 120 Hz. The "Stability" figure is the share of frames that landed within 10% of the typical interval — high means a locked, consistent rate.
Why might the reading look off?
- Keep this tab focused — background tabs are throttled and will read low.
- On a laptop, plug in. Many switch to 60 Hz on battery to save power, and some browsers cap the animation clock at 60 Hz regardless of the panel.
- Variable refresh rate (G-Sync / FreeSync / ProMotion) can make the rate fluctuate, which shows up as a lower stability and a wider histogram.
- With multiple monitors, the result reflects the display this browser window is on.
Frequently asked questions
What does refresh rate (Hz) mean on a monitor?
Refresh rate is how many times per second your display redraws the image on screen, measured in hertz (Hz), so a 60 Hz monitor updates 60 times per second and a 144 Hz monitor 144 times. It is a timing metric, not a picture-quality one like color or contrast: a higher rate makes motion look smoother because each step between updates is smaller. A browser test estimates this by timing how often the display can present new frames.
What's the difference between refresh rate (Hz) and frame rate (FPS)?
Frame rate (FPS) is how many frames your GPU produces each second, while refresh rate (Hz) is how many times your monitor can actually display a new frame. They are related but separate: the monitor's Hz sets the ceiling, and your system needs enough FPS to fill it. A browser-based test measures the display side (Hz) by timing how frequently frames are shown, not how many a game can render.
Is the difference between 60Hz, 120Hz, 144Hz, and 240Hz noticeable?
The jump from 60 Hz to 120 Hz or 144 Hz is the most obvious to most people, with visibly smoother motion and less blur in fast-moving content. Going from 144 Hz to 240 Hz is a smaller, more subtle improvement that mainly benefits fast-paced gaming, and how much you notice it is somewhat subjective. Higher rates also slightly reduce the delay before your actions appear on screen, since the display updates more often.
Why does a browser refresh rate test show 60Hz on my 144Hz monitor?
Browser tests rely on the requestAnimationFrame timing, which usually matches your display but can be capped at about 60 Hz by software rather than the panel itself. The most common cause is that your operating system is still set to 60 Hz, so check Windows Display settings or macOS Displays first. Other causes include Safari's default "Prefer Page Rendering Updates near 60fps" flag, a laptop throttling on battery, a background or inactive tab, or a cable that can't carry the higher rate.
What is variable refresh rate (G-Sync, FreeSync, ProMotion)?
Variable refresh rate (VRR) lets the display change its refresh rate on the fly to match the frame rate your GPU is producing, which reduces screen tearing and stutter. NVIDIA G-Sync, AMD FreeSync, and HDMI VRR are built for monitors and TVs, while Apple's ProMotion does the same on supported iPhones, iPads, and MacBook Pros, scaling up to 120 Hz. Because the rate fluctuates with VRR active, a browser test may report a varying number, so it reads the panel's true maximum most reliably when the on-screen frame rate is steady and high.
How do I change or enable a higher refresh rate on Windows and Mac?
On Windows, go to Settings > System > Display > Advanced display and pick the highest value under "Choose a refresh rate"; if higher options are missing, check your cable, GPU driver, and the GPU control panel. On macOS, open System Settings > Displays and choose from the Refresh Rate menu, holding Option while clicking it to reveal extra options on some models. On a MacBook Pro, ProMotion provides an adaptive rate up to 120 Hz rather than a fixed value, and after changing settings you can confirm the result with an in-browser refresh rate test.