Screen Tearing Test

What tearing is

A display redraws itself line by line, many times a second. If a new frame arrives while the screen is part way through a redraw, the top of the screen shows the old frame and the bottom shows the new one. On a moving vertical edge, that shows up as a horizontal break, with the bar above the break sitting slightly to one side of the bar below it.

1. 1

   Open the test full screen and press Start.

2. 2

   Watch the bar's vertical edges, not the middle. A tear looks like a step in the edge that jumps around or stays at one height.

3. 3

   Look for a minute. Tearing can come and go as frame timing drifts.

What a browser can and cannot show

Browsers usually hand their frames to the system in step with the display, so a browser page often shows no tearing at all, even on a setup where games tear badly. A clean result here is therefore good news but not proof. Games and video players have their own settings: V-Sync, "wait for vertical refresh", and variable refresh technologies such as G-Sync and FreeSync, which change frame timing directly.

If the bar stutters rather than tears, check the frame rate with the Refresh Rate Test. For blur and ghosting instead of tearing, use the Motion Blur / UFO Test. Refresh Rate Explained explains where tearing comes from.

If you see tearing

Tearing is a timing problem, not a panel fault. In a game, turning on V-Sync removes it at the cost of a little input delay. If your display and graphics card both support variable refresh, turning it on in the display's menu and in the graphics driver usually removes tearing without that delay. Capping a game's frame rate a little below the refresh rate also helps.