Size the disk a security camera system needs for a chosen retention window, bitrate and number of cameras.
Bitrate in Mbps times seconds of recording gives megabits, which divided by 8,000 gives gigabytes. Multiplying by device count and retention days gives the array size, and the saving factor accounts for motion-triggered recording or smarter codecs. Retention promises are a storage commitment: undersizing the array silently shortens the window, and a missing camera recording is only discovered when it is needed.
Security Camera Storage
Storage (GB) = bitrate × 3600 × hours ÷ 8000 × devices × days × (1 − saving)
Storage (GB) = bitrate × 3600 × hours ÷ 8000 × devices × days × (1 − saving) Bitrate in Mbps times seconds of recording gives megabits, which divided by 8,000 gives gigabytes. Multiplying by device count and retention days gives the array size, and the saving factor accounts for motion-triggered recording or smarter codecs.
Retention promises are a storage commitment: undersizing the array silently shortens the window, and a missing camera recording is only discovered when it is needed.
This calculator takes 5 inputs: Number of cameras, Bitrate per camera, Recording hours per day, Retention period, Saving from motion detection or compression. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.