size → bitrate
Video bitrate calculator
Enter how long the video is and how large it is allowed to be. The calculator returns the video bitrate to set in OBS, HandBrake, Premiere or any encoder.
Calculated in your browser · nothing is sent anywhere
What bitrate actually controls
Bitrate is how many bits the encoder is allowed to spend on each second of video. It is the single number that decides file size: multiply bitrate by duration and you have the size, near enough.
Working backwards from a size limit is the common case. An upload cap, an email attachment, a chat platform tier — all of them state a size, and the encoder wants a bitrate. That conversion is what this page does.
The audio field matters more than people expect on short clips. At 128 kbps, audio eats a meaningful share of a small budget, and for speech-only recordings dropping it to 96 or 64 kbps frees real room for the picture.
A sanity check on the result
If the number comes out under about 1000 kbps for 1080p footage, the video will look visibly soft. Either shorten the clip or drop the resolution to 720p, where the same bitrate stretches much further. Bitrate targets are always relative to how many pixels have to be described.
Once you know the bitrate you need, apply it with compress video.
Common questions
Why is my real file slightly different?
Encoders aim at a target rather than hitting it exactly, and container overhead adds a little. Expect within a few percent.
Should I use CBR or VBR?
For hitting a size target, constant bitrate is more predictable. Variable bitrate gives better quality per byte but overshoots and undershoots.
What bitrate is good for YouTube?
YouTube re-encodes everything anyway, so upload at a high bitrate and let it do the work. Around 8000 kbps for 1080p is plenty.
Is any data sent anywhere?
No. This is arithmetic running in your browser.