Test Refresh Rate

Your monitor redraws its entire image a fixed number of times each second, known as its refresh rate. A 60Hz screen redraws 60 times a second, while a 144Hz gaming monitor does it well over twice as often. Windows, macOS, and even a loose cable can quietly cap that rate below what your hardware actually supports, so the number in your display settings is not always the number you are really getting.

This test uses the browser's requestAnimationFrame clock to time the gap between one rendered frame and the next, over and over, while a bar moves continuously across the screen. Because the browser can only draw as fast as your monitor redraws, the shortest and most consistent gaps between frames reveal your true refresh interval. Occasional slower gaps, caused by a busy tab or background task, only make that gap longer, never shorter, so the test leans on the tightest cluster of readings rather than a simple average.

Once enough consistent samples come in, the measured interval is converted into Hz and checked against common display rates, including 60Hz, 90Hz, 120Hz, 144Hz, 165Hz, and 240Hz, to show you the closest standard match. A confidence label tells you whether the reading is still settling or steady enough to trust.

Everything runs locally in your browser tab, and the test stops the moment you close it or switch away.