How the estimate works
The calculator converts the configured bitrate into gigabytes per day, multiplies it by the number of cameras, retention period, and active recording percentage, then adds 15% headroom. Variable bitrate streams can move above or below the estimate as scene detail and motion change.
Use the camera's stream settings when possible
Resolution alone does not determine storage. Frame rate, codec profile, image noise, keyframe interval, and bitrate limits all matter. A noisy night scene can consume more space than a well-lit static scene at the same resolution.
Choosing storage hardware
Round up after accounting for RAID. For example, a mirrored pair provides about one drive's worth of usable capacity, while parity arrays reserve capacity for recovery. Surveillance-rated drives are designed for sustained recording workloads, but the recorder's drive compatibility list should still be checked.
Planning a broader system? Compare our home security camera picks, microSD cards for 4K recording, and home server build guide.
Important limits
This is a capacity estimate, not a guarantee. Test the actual stream settings and retention behavior before relying on the system for critical footage. Reserve separate capacity for operating systems, databases, thumbnails, exports, and snapshots.