🎬 Video
Video Bitrate to File Size
Work out how large a video will be from its bitrate, or the bitrate you need to hit a target size. Add audio and overhead, then press Convert.
About the Video Bitrate to File Size
Video file size is bitrate × time. A 10 Mbps video for 60 minutes is 10 megabits every second for 3,600 seconds, or 36,000 megabits — 4,500 megabytes at decimal units. Audio and container overhead add to that, which is why a '10 Mbps' export is never exactly 4.5 GB per hour.
This calculator works in decimal megabytes and gigabytes, the units drives and streaming platforms use. If your editing software reports GiB (1,024 MiB), the number will be about 7% larger for the same byte count. Variable-bitrate footage will also differ from the average you enter.
How the calculation works
- Size (bytes) = total bitrate (bits/s) × duration (s) ÷ 8.
- Total bitrate = video bitrate + audio bitrate.
- Container overhead is applied as a percentage of the muxed stream.
- Required total bitrate = target bytes × 8 ÷ duration ÷ (1 + overhead).
Reference values
| Video bitrate | 1 minute | 1 hour | 2 hours |
|---|---|---|---|
| 2 Mbps | 15 MB | 0.90 GB | 1.80 GB |
| 5 Mbps | 37.5 MB | 2.25 GB | 4.50 GB |
| 10 Mbps | 75 MB | 4.50 GB | 9.00 GB |
| 25 Mbps | 187.5 MB | 11.25 GB | 22.50 GB |
| 50 Mbps | 375 MB | 22.50 GB | 45.00 GB |
Worked example: a one-hour 10 Mbps export
A 60-minute video at 10 Mbps video plus 192 kbps audio is (10,000,000 + 192,000) × 3,600 ÷ 8 = 4.586 GB, before container overhead. At 20 Mbps it is 9.086 GB. A 4 GB upload limit therefore allows about 52 minutes at 10 Mbps, not a full hour.
Variable-bitrate encoding can beat those estimates on simple footage and exceed them on busy footage. Container overhead, multiple audio tracks and metadata add a little more. If a platform has a hard limit, encode a short test clip at the target settings and measure the actual file size before exporting the full programme.