Video Bitrate File Size Budget Calculator
Translate a bitrate budget into a rough encoded file size before recording or exporting. The overhead allowance is your input rather than a hidden container preset.
Method, example, and limits
Formula: Bytes ≈ (video kb/s + audio kb/s) × 1000 × seconds × (1 + overhead/100) ÷ 8.
Inputs and units: Bitrate inputs use decimal kilobits per second; duration is seconds; overhead is an added percentage. Results show MB (1,000,000 bytes) and MiB (1,048,576 bytes).
Worked example: At 8,000 kb/s video, 192 kb/s audio, 3,600 seconds, and 3% overhead, estimate 3,796.992 MB or about 3,621.094 MiB.
Assumptions: The entered bitrates are average rates over the full duration, and overhead percentage applies to the combined stream. Zero duration produces zero estimated bytes.
Limits: Variable bitrate, metadata, muxing, headers, subtitles, filesystem allocation, and encoder behavior can shift actual size. The estimate does not enforce a target-quality bitrate.
Creator & reviewers
Creator persona
- Casey RowanUnits, conversions & measurement
Reviewer personas
- Devon ShawFormula & assumptions review
- Sage MitchellClarity & usability review