About TrueHz

TrueHz is a free online tool that measures your monitor or screen's real refresh rate and helps you inspect the overall quality of your display — all directly in your browser, with nothing to download and nothing to sign up for.

Why we built it

Plenty of people buy a 120 Hz, 144 Hz, or 240 Hz monitor and never confirm it's actually running at full speed. Operating systems often default new displays to 60 Hz, and the wrong cable or driver can quietly cap your refresh rate. Most existing refresh-rate tools were either inaccurate, cluttered, or hard to trust. We wanted a fast, accurate, good-looking tool that simply tells you the truth about your screen.

How it works

Rather than reading a value from your system settings, TrueHz samples real rendered frames using the browser's frame-timing API and converts the interval between frames into a precise refresh rate in hertz. A Precision mode averages 30 seconds of frames for an even more reliable reading. The same engine powers our resolution, color, and fullscreen panel tests.

What you can test

• Refresh rate — your screen's true Hz, measured live.
• Display info — resolution, pixel ratio, color depth, gamut and more.
• Dead & stuck pixels — fullscreen solid colors to spot defects.
• Color banding & gradients — reveal bit-depth limits.
• Backlight uniformity — check bleed and brightness evenness.
• Motion & ghosting — judge blur and response time.
• Contrast, gamma & sharpness — evaluate panel clarity.

Privacy first

Everything runs locally in your browser. Your measurements and display data are never uploaded or stored — there are no accounts and no tracking of your results. You can even use the tool offline.