How the frame rate is measured
This page asks the camera for 60 fps at 1280×720, the size at which most webcams that can do 60 fps offer it. The Frame rate box next to the preview then shows two numbers:
- Measured: the frames that actually reached the page, averaged over the last five seconds.
- Camera reports: the rate the camera says it is set to.
If your camera tops out at 30 fps, it simply opens at 30, and that is the right result for it. Switch Frame rate to 30 fps or Resolution to 1080p to compare modes; the count starts over after each change.
Reading the result
- Measured close to reported (within a frame or two): the camera delivers what it promises.
- Measured about half the reported rate: the classic sign of low light. At 60 fps each frame can be exposed for a sixtieth of a second at most, so in a dim room the camera stretches the exposure and drops frames. Add light in front of you and watch the number climb. The C922 test goes through Logitech’s own lighting advice for 60 fps.
- Low at every size and in bright light: look at the connection and the computer: a USB hub or extension, another app holding the camera, or a CPU busy with something else.
- Jumpy numbers: a few seconds after a change are normal. If the rate keeps jumping by more than a few frames, the camera or its connection is struggling.
Before a stream or a call
Run the test with the room lit the way it will be when you go live, not in daylight beforehand: the frame rate depends on the light at that moment. To check the picture size rather than its smoothness, use the webcam resolution test.