Video · Free browser tool
Video bitrate calculator for a target file size
File size is approximately combined audio/video bitrate multiplied by duration, divided by eight. Reserve an allowance for overhead, then subtract audio bitrate to find the video budget.
No account required. File and text processing stays in your browser.
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How to use it
- 01
Choose the calculation
Fit a target size or estimate a file from its bitrates. Use the actual video duration in seconds.
- 02
Allow for audio
Enter audio bitrate and an overhead allowance. MB and MiB represent different byte counts.
- 03
Test the export
Use the result as an encoding budget, then measure the actual output. Variable bitrate and container overhead can change the final size.
A worked example
For 180 seconds at 4 Mbps video plus 192 kbps audio, the payload estimate is 94.32 MB before overhead.
What to check
- This calculates a size budget, not a quality guarantee. Fine screen text may need a different composition or a larger file.
- The allowance reserves a percentage of the total target. Actual container overhead is not measured by this calculator.
- No media is required; calculations use only the numbers you enter.
Questions
Will this make an exact-size file?
No. It is a planning estimate. Leave margin below a strict limit and inspect the encoded file before submission.
What is the difference between MB and MiB?
One decimal MB is 1,000,000 bytes; one MiB is 1,048,576 bytes. Choose the unit used by your upload destination.
Continue the workflow
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