Video File Size Calculator
Estimate how large a video file will be from its duration and bitrate, or reverse the calculation to find the bitrate that fits a target file size. Everything runs in your browser.
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Higher bitrate means better quality and a larger file.
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Estimated file size
Main result
0 MB
In other unit
0 GB
The formula
Video file size is calculated with this simple formula:
File size (megabits) = bitrate (Mbps) × duration (seconds)
Divide the result by 8 to get megabytes, and by 1024 to get gigabytes:
Size (MB) = bitrate (Mbps) × duration (seconds) ÷ 8
Audio bitrate is added to the video bitrate before the calculation. Actual exported files can differ slightly because every encoder and container stores a little extra metadata.
Frequently asked questions
For 1080p video, 8 to 12 Mbps looks good for most content. Fast-moving content like sports or games may need 12 to 16 Mbps, while a simple talking-head video can look fine at 5 to 6 Mbps.
Only up to a point. Beyond a certain bitrate the human eye can no longer see the difference, so extra bitrate only makes the file larger. The presets on this page are good starting points for each resolution.
Encoders add container overhead and metadata, and variable bitrate encoding can spike above your target during complex scenes. Choose an overhead option above for a closer estimate.