What it does
Work in either direction
Estimate file size from duration and bitrate, work backward from a file-size limit, or find duration from a known file size and bitrate.
Export planning
Video File Size & Bitrate Calculator
Plan an export from the values you already know—duration, bitrate, file-size limit, or upload speed.
Calculator
Choose what you need to find
All file sizes use SI decimal units: 1 MB is 1,000,000 bytes and 1 GB is 1,000,000,000 bytes.
Core relationship
The formula
file size (bits) = total bitrate (bits/s) × duration (seconds)
The calculator uses decimal MB and GB, converts all values to bits internally, and rounds only for display.
Example
A practical export
A 10-minute video with 8 Mbps video and 320 kbps audio is approximately 624 MB, or 0.624 GB, before container overhead.
Related tools
Use the bitrate in your next export step
Check whether that bitrate matches current YouTube guidance, or confirm the resolution you plan to deliver.