File Size Calculator
Predict file size before you render.
Enter a video's bitrate and its length in minutes to estimate the resulting file size. Useful before rendering, streaming, or uploading — nobody wants a surprise 20 GB upload. The calculator shows both megabytes and gigabytes so you can judge against your storage and data caps.
How it's calculated
File size = bitrate (Mbps) × minutes × 60 ÷ 8 megabits per byte, giving megabytes, then ÷ 1,024 for gigabytes.
Frequently asked questions
What is video bitrate?
Bitrate is how much data each second of video uses, measured in megabits per second. An 8 Mbps stream uses 8 megabits every second — multiply by the duration for the file size.
Can I estimate a short clip under a minute?
Yes — just type 0.17 for 10 seconds (10 ÷ 60). The math works the same for clips of any length.
Is this the exact final file size?
It is close. Container overhead and variable bitrate encoding add a few percent, but this estimate is accurate enough for planning storage and uploads.