Try the calculator
Runs in your browser. No signup, upload or saved inputs.
When this is useful
A bitrate budget helps you choose a starting encode, but it does not tell you whether the interface will remain readable. Duration and source complexity still need editorial and visual review.
How to use this calculator
- Enter a target size in decimal MB and the intended duration in seconds. Use a budget below any hard upload ceiling to leave room for overhead.
- Enter audio bitrate in kbps. The calculator subtracts its estimated payload from the total before calculating video Mbps.
- If no video budget remains, reduce duration or audio needs, or increase the size budget. Otherwise, test a short encode at the calculated bitrate and inspect text and motion.
Worked calculation
An illustrative 30 MB media budget over 60 seconds permits 4 Mbps in total. After reserving 128 kbps for audio, the estimated video budget is 3.872 Mbps. Container overhead would require additional headroom.
Formula and units
Video Mbps = target MB × 8 ÷ seconds − audio kbps ÷ 1000.
Limits and checks
The tool rejects a budget that is entirely consumed by audio. It does not predict constant-quality encoding size or guarantee a particular visual quality. Use the actual final file for the acceptance check.
Your next step
Compare the estimated bitrate with a representative export and shorten or reframe the story if the available detail is insufficient.
References and scope
Examples are illustrative production guidance, not measured customer results. General workflows are not promises of product compatibility. Read our editorial approach and current Demovela scope.