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Adaptive Sync (G-Sync / FreeSync) Test
Sweeps the frame rate up and down so you can see whether your variable-refresh display is smoothing it or stuttering.
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The test starts automatically — follow the prompts above.
In short
Adaptive sync — G-Sync on Nvidia hardware, FreeSync on AMD, and VRR generically — lets the display change its refresh rate to match the frame rate instead of the other way round, which removes tearing without the latency V-Sync adds. This sweeps the frame rate up and down so you can see whether it is working. With adaptive sync active, motion stays smooth through most of the sweep and breaks up only at the very bottom, where the frame rate drops below the panel's minimum VRR frequency — usually somewhere between 30 and 48 Hz. Without it, you get tearing or stutter throughout. No website can detect adaptive sync directly, because no browser API exposes it, so this is a visual comparison rather than a readout: run it with the feature on and off and compare. The commonest reason it appears not to work is that it is enabled in one place and not the other — it usually has to be switched on in the graphics driver AND in the monitor's own on-screen menu, and the monitor side is off by default on many models.
How to use the Adaptive Sync (G-Sync / FreeSync) Test
- The test starts on its own — no button to press and nothing to install.
- Follow the prompt in the test panel and watch the readings update live.
- Press Reset to start over with a clean slate.
About the Adaptive Sync (G-Sync / FreeSync) Test
The Adaptive Sync (G-Sync / FreeSync) Test sweeps the frame rate up and down so you can see whether your variable-refresh display is smoothing it or stuttering. It runs as plain JavaScript inside the page, which means there is no upload step, no queue and no size limit imposed by a server — the only limit is your own device.
What people use it for
- Confirming G-Sync or FreeSync is switched on and working.
- Finding the frame rate at which your panel stops smoothing.
Where this tool stops
A visual check. Browsers cannot query adaptive-sync state, and the frame pacing a page can request is coarser than a game engine's.
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Frequently asked questions
What should I see if adaptive sync is working?
Smooth motion through most of the sweep, breaking up only at the very bottom where the frame rate drops below the panel's minimum VRR frequency — usually around 48 Hz.
Can a website detect G-Sync directly?
No. There is no browser API for it, so this is a visual comparison rather than a readout. Run it with adaptive sync on and off to see the difference.
Is the Adaptive Sync (G-Sync / FreeSync) Test free, or is there a paid tier?
It is free, with no account, no trial and no daily cap. Every screen tests tool on inputtesthub.com works the same way: open the page and use it.
Does anything I enter leave my computer?
No. The Adaptive Sync (G-Sync / FreeSync) Test runs entirely in your browser using JavaScript. Because the work happens locally, the page also keeps working if your connection drops, and closing the tab is all it takes to discard everything.
What do people use the Adaptive Sync (G-Sync / FreeSync) Test for most?
The most common reasons people reach for it: confirming G-Sync or FreeSync is switched on and working. Finding the frame rate at which your panel stops smoothing. It is built for exactly those cases rather than being a general-purpose tool with this bolted on.
When is the Adaptive Sync (G-Sync / FreeSync) Test not the right tool?
A visual check. Browsers cannot query adaptive-sync state, and the frame pacing a page can request is coarser than a game engine's. Knowing where a tool stops being trustworthy matters more than the cases where it works.
Why does the test start on its own?
No installation, no extension and no driver. The Adaptive Sync (G-Sync / FreeSync) Test uses the browser's own device APIs and begins as soon as the page loads, so there is nothing to press first. Press Reset at any point to start over with a clean slate.
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