Frame rate checker
Check the frame rate of a video in your browser — the file never leaves your device.
Drop a video and its frame rate comes from the time stamp of every frame in the file, not from a label in the header. That is how the page can say whether the rate is constant or variable, and over what range a variable one moves.
24, 25, 30, 60 — and 29.97
Film is shot at 24 frames a second, European television runs at 25 and 50, and American television and most phones at 30 and 60. Cameras still use 23.976, 29.97 and 59.94 — 1000/1001 of the round numbers, a leftover from colour television — and editors keep them so the sound stays in step. The page names the standard rate when a file has one.
Constant and variable frame rate
Phones often record a variable frame rate: when the light drops, for instance, a phone can hold each frame longer, so the rate slides from 30 to 20 or lower. Players do not mind, but editing software can drift out of sync with the sound, which is why the page says when a file is variable and how far its rate moves.
What it reads
MP4, MOV, 3GP, MKV, WebM and AVI are read directly from their frame tables, in milliseconds; other formats can be read with ffmpeg. The frame count and the duration come from the same tables, so the average rate is simply the frames divided by the time they span.
How to use it
- Add a video file.
- Read the frame rate and whether it stays constant.
- For a variable rate, see the range it moves through.
Why use this tool
Completely private
Everything runs inside your browser. Your files and text are never sent to a server.
Free, with no limits
No sign-up, no watermarks and no cap on how many times you can use it.
Instant results
There is no upload or queue to wait for, so results appear as fast as your device can work.
Works on any device
Runs in any modern browser on phone, tablet or desktop. Nothing to install.
Frequently asked questions
- How do I check the frame rate of a video?
- Drop it here: the frame rate, whether it is constant and the number of frames appear at once. On Windows, a video’s Properties › Details shows a frame rate too, but not whether it varies.
- What is the difference between 29.97 and 30 fps?
- 29.97 is 30 × 1000/1001 — the rate American colour television settled on in 1953, which cameras and editors still use. Over an hour, 29.97 fps shows about 108 fewer frames than 30. They look the same; what matters is not mixing them in one edit.
- What is variable frame rate?
- A video whose frames are not evenly spaced in time — common from phones and screen recorders. It plays fine, but editing software can lose sync with the sound; converting it to a constant rate before editing avoids that.
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