Video Frame Rate Checker
Find your video's fps without uploading it. Drop an MP4, MOV, MKV, WebM, or AVI below and the tool reads the frame rate straight from the file's metadata, in your browser. It also flags variable frame rate (VFR), where a simple subtitle conversion won't help.
How it reads the frame rate (and why nothing uploads)
Every video container records its frame timing in a small metadata header — the moov atom in MP4 and MOV, the Tracks element in MKV and WebM, the stream header in AVI. This tool reads only those header bytes from the file on your device, the same way the subtitle extractor reads container headers, so even a multi-gigabyte movie is inspected in place. The file is never uploaded or copied to a server.
MP4 and MOV give an exact reading, down to telling 23.976 from 24. AVI is exact too and is constant by format. MKV and WebM report a nominal rate: the container stores a single default frame duration but does not record in its header whether the real timing stays constant, so that figure is a best indication rather than a guarantee.
Know your fps and need to line up subtitles? Fix subtitle framerate drift →
FAQ
How do I check my video's frame rate?
Drop the video file onto this page or click to choose one. The tool reads the frame rate straight from the file's metadata in your browser and shows it, for example 23.976 fps or 25 fps. Nothing is uploaded and no software is needed.
What is variable frame rate (VFR)?
A variable-frame-rate video changes how many frames it shows per second over its length, instead of holding one constant rate. Phone and screen recordings are commonly VFR. It matters for subtitles because the drift it causes is not a single constant ratio, so a framerate conversion cannot fix it — the video has to be converted to a constant frame rate first, in a tool like HandBrake.
Which video formats can it read?
MP4 and MOV are read exactly, including reliable VFR detection. AVI is read exactly and is constant by format. MKV and WebM report their nominal frame rate; the format does not record constant-versus-variable in the header, so that figure is nominal. The tool parses the metadata itself, so it works even for containers a browser cannot play.
Is my video uploaded anywhere?
No. The file never leaves your device. The tool reads only small slices of the metadata locally in JavaScript, so even multi-gigabyte videos are checked in place without uploading or copying them.