Video File Size Calculator
Enter your resolution, frame rate, codec and recording time — get the exact storage you'll need, the data rate, and the right SD card speed class, in real time.
Your shoot
How video file size is calculated
Every video file boils down to one simple relationship between its bitrate and its length:
The bitrate is the number of megabits the camera records each second. It rises with resolution (more pixels), frame rate (more frames per second) and the codec you choose — lightly-compressed formats like ProRes or RAW use far higher bitrates than delivery codecs like H.264 or H.265. Multiply that bitrate by the recording time, divide by 8 to turn bits into bytes, and you have the file size. We also surface the data rate (MB/s), because that's what actually decides which memory card is fast enough to keep up.
Example: file size of 10 minutes in 4K
Say you're shooting 4K UHD at 30 fps in H.265 for 60 minutes:
- H.265 at 1080p30 is 50 Mbps; ×4 for 4K resolution = 200 Mbps at 30 fps.
- 200 Mbps × 3,600 s ÷ 8 = 90,000 MB ≈ 90 GB for the hour.
- Data rate = 200 ÷ 8 = 25 MB/s → a V30 card handles it; you'd want a 128 GB card.
Switch the codec to ProRes 422 HQ (880 Mbps) and the same hour jumps to about 396 GB at 110 MB/s — beyond SD-card territory: you'd need CFexpress Type A or an external SSD.
Quick reference table
Approximate size per minute and per hour at 30 fps with H.264 / H.265 (no audio). Double the values at 60 fps:
| Resolution | Bitrate | Per minute | Per hour |
|---|---|---|---|
| 720p | 22 Mbps | 165 MB | 9.9 GB |
| 1080p | 50 Mbps | 375 MB | 22.5 GB |
| 1440p | 89 Mbps | 668 MB | 40 GB |
| 4K UHD | 200 Mbps | 1.5 GB | 90 GB |
| 6K | 450 Mbps | 3.4 GB | 203 GB |
| 8K UHD | 800 Mbps | 6 GB | 360 GB |
Efficient codecs AV1 and VP9 shave ~10-20%; editing codecs blow it up: at 4K30, ProRes 422 ≈ 265 GB/h, ProRes 422 HQ and DNxHR ≈ 396 GB/h, and Blackmagic RAW ≈ 198 GB/h. Use the calculator above for your exact combination.
Methodology & sources
Every result is computed in your browser with the formula shown above — nothing is sent to a server. The numeric model is based on this data and these references:
- SD Association — Video Speed Classes (V30/V60/V90)
- CompactFlash Association — CFexpress specification
- Apple ProRes — White Paper (data rates per variant)
- Typical average bitrates per codec (H.264/H.265, DNxHR, Blackmagic RAW) from manufacturer documentation.
- Commercial card capacity computed reserving ~7% for filesystem formatting.
Formula reviewed and verified against real-world cases.