Technology
Video File Size Calculator
Estimate video file size from resolution, bitrate, codec, and duration. Compare codec efficiency side by side.
Common: 720p=5, 1080p=8, 1440p=16, 4K=35
Enter video details and click Calculate
How is this calculated?
File Size (MB) = Bitrate (Mbps) × Duration (seconds) ÷ 8
Codec Efficiency (relative to H.264 at same quality):
H.264: 1.0× (baseline)
H.265: 0.65× (35% smaller)
VP9: 0.65× (35% smaller)
AV1: 0.50× (50% smaller)
Audio adds ~128-320 kbps (typically 1-2 MB/minute)
Container overhead: ~1-2% additionalFAQ
Frequently asked questions about video file sizes
How do I calculate video file size?
File Size (MB) = Bitrate (Mbps) × Duration (seconds) ÷ 8. For example, a 10-minute video at 8 Mbps = 8 × 600 ÷ 8 = 600 MB.
What bitrate should I use for YouTube?
YouTube recommends 8 Mbps for 1080p, 16 Mbps for 1440p, and 35-45 Mbps for 4K uploads. For HDR content, increase by 25-50%.
Which codec produces the smallest files?
AV1 produces the smallest files (30-50% smaller than H.264), followed by H.265/HEVC (25-40% smaller than H.264). VP9 is similar to H.265. H.264 is the largest but most compatible.
Does resolution directly affect file size?
Higher resolution requires higher bitrate for the same quality. 4K at similar quality needs roughly 4× the bitrate of 1080p, resulting in 4× larger files.
What's the difference between CBR and VBR?
CBR (Constant Bitrate) produces predictable file sizes but wastes space on simple scenes. VBR (Variable Bitrate) is more efficient, allocating bits where needed.
How much storage do I need for video production?
Raw 4K footage at ProRes 422: ~110 GB/hour. H.264 4K at 100 Mbps: ~45 GB/hour. Compressed H.265 4K at 35 Mbps: ~16 GB/hour. Always budget 2-3× raw footage for editing workspace.