What is the Video File Size Calculator?
The Video File Size Calculator is a pre-production tool for videographers and editors. It forecasts the massive hard drive space required to shoot a specific duration of video, allowing you to buy enough SD cards before a wedding shoot or ensure you have enough cloud storage for export.
How to Calculate Video Storage Requirements (Formulas)
Resolution (1080p vs 4K) does not technically determine the file size. The file size is determined entirely by the "Bitrate" (the amount of data processed per second) chosen in the camera menu.
- Bitrate Conversion: Megabits per second (Mbps) / 8 = Megabytes per second (MB/s).
- File Size Formula (MB): Duration of video in seconds * Bitrate in MB/s.
- Example: 1 minute (60 seconds) of 4K video shot at 100 Mbps (12.5 MB/s) will consume exactly 750 Megabytes of storage.
Frequently Asked Questions
Why is my iPhone 4K video file so much smaller than my Sony 4K video?
Smartphones use extreme, highly efficient compression algorithms (like HEVC/H.265) and very low bitrates (around 25 Mbps) to save storage space on your phone. A professional Sony cinema camera shoots 4K using massive, low-compression codecs (like ProRes or XAVC-S) at 400 Mbps to capture incredible color data for editing, resulting in file sizes that are 10 times larger for the exact same duration.
What is 10-bit color and why does it take up so much space?
Standard 8-bit video can display 16 million colors. Professional 10-bit video can display 1 billion colors, eliminating color banding in smooth skies. Storing the data for those extra 984 million colors requires a significantly higher bitrate, drastically increasing the final file size.
Should I shoot in RAW video?
Shooting RAW (like REDCODE RAW or BRAW) captures the pure, uncompressed sensor data, allowing for unparalleled color grading flexibility in post-production. However, RAW video files are astronomically huge. A single hour of RAW 4K footage can easily consume 1 Terabyte (1,000 Gigabytes) of extremely expensive SSD storage.