Video Bitrate File Size Calculator
Estimate video file size from video bitrate, audio bitrate and duration, with decimal GB, binary GiB and storage-per-minute outputs.
Estimate video file size from bitrate
Convert video and audio bitrate plus duration into an approximate file size.
How the Video Bitrate File Size Calculator works
The core relationship is file size = bitrate × duration ÷ 8 because bitrate is normally expressed in bits per second while storage is measured in bytes. The calculator adds video bitrate in Mbps and audio bitrate converted from kbps, then reports decimal gigabytes, binary gibibytes and storage used per minute.
How to use this video bitrate file size calculator
Enter an average video bitrate, audio bitrate and clip duration. For constant-bitrate exports, the entered value is straightforward. For variable-bitrate encodes, use the measured or target average bitrate rather than the maximum setting. This makes the result useful for upload planning, recording-time estimates and archive capacity.
How to interpret the result
At the same bitrate and duration, two codecs produce roughly the same file size even if their visual quality differs. Resolution, frame rate, bit depth and codec efficiency influence how much bitrate is needed to achieve a quality target, but they do not independently enter the basic size equation once bitrate is known.
Assumptions and limitations
Container headers, metadata, multiple audio tracks, subtitles and muxing overhead add some data. VBR footage can also miss the target average. Camera “Mbps” labels may include or exclude audio depending on the manufacturer. For guaranteed recording duration, leave safety margin rather than filling a card to the calculated limit.
Practical example and workflow
A 10-minute clip at 20 Mbps video plus 192 kbps audio is about 1.5 GB before small container overhead. An editor comparing a 20 Mbps and 50 Mbps export can immediately see the storage/upload difference without guessing from resolution alone.