VIDEOTOOLS

How to Estimate Video File Size

Master the bitrate × duration formula, container overhead, and storage units.

Bitrate × time determines the data budget

Bitrate measures bits written per second. Multiply average video bitrate by duration in seconds, add audio bitrate, and divide by 8 to get bytes.

For example: 10 Mbps video + 128 Kbps audio for 1 hour (3,600s) = (10,000,000 + 128,000) × 3,600 ÷ 8 = 4.56 GB before container overhead.

Container overhead

Containers (MP4, MOV, MKV) add header indices, timecodes, and metadata (typically 0.5% to 2%). VideoTools includes an adjustable overhead factor.

Decimal MB vs. Binary MiB

Decimal MB divides bytes by 1,000,000; Binary MiB divides by 1,048,576. Storage manufacturers use decimal MB/GB, while operating systems often use binary.

Last reviewed: September 21, 2026. VideoTools creator toolkit.