Video

Bitrate calculator.

Enter the file size you're targeting and how long the video runs, and get the bitrate to encode at — split into a video allowance and an audio allowance, in kbps and Mbps.

Inputs

Set a target size and duration; the recommended bitrate updates instantly.

Target file size

Decimal units: 1 MB = 1,000,000 bytes, 1 GB = 1,000 MB — the convention bitrate math (kbps/Mbps) is defined in, not the binary MiB your OS shows for file sizes.

Duration

Hours

Minutes

Seconds

Audio bitrate to reserve Subtracted from the total so the video track alone doesn't overshoot the target size.

Result

Enter a size and duration to see the recommended bitrate.

How it works

Formula: total bitrate (bits/second) = target size in bytes × 8 ÷ duration in seconds — the standard bit-rate definition documented on Wikipedia. The video bitrate is that total minus the audio bitrate you reserve.
For reference: per YouTube's recommended upload encoding settings, SDR uploads at standard frame rate are roughly 8 Mbps at 1080p, 5 Mbps at 720p, and 35–45 Mbps at 4K — use those as a sanity check against whatever this calculator recommends for your target size.
Container overhead: not modelled here — MP4/MKV muxing overhead is small (typically well under 1%) next to the video and audio streams themselves, so the true output size will usually land a little under your target, not over it.

Limits

Pure arithmetic, no upload, no file processing.