💾 Video File Size Calculator
Enter your video’s duration and bitrate settings to estimate the resulting file size in megabytes and gigabytes.
What this calculator does
The Video File Size Calculator estimates how large a video file will be based on its duration and the bitrates used for its video and audio streams.
How the calculation works
File size depends on how much data is recorded per second (bitrate) and for how long. The calculator multiplies video bitrate and audio bitrate separately by the duration in seconds to get total bits, adds them together, then converts bits to bytes (dividing by 8) and bytes to megabytes or gigabytes (dividing by 1,048,576 and again by 1,024). This mirrors how video encoders and editing software estimate export sizes.
This is an estimate for general planning and storage-budgeting purposes. Actual file sizes can vary with variable bitrate encoding, container overhead, and codec efficiency, so treat the result as a close approximation rather than an exact figure.