Define the operational requirement
Decide how many days of ordinary footage must remain available, whether recent footage needs full quality, and how incidents will be preserved beyond routine retention. A residence, retail site and gated property may have different priorities even with the same number of cameras.
Capacity estimates are planning values
Estimator results depend on camera and recording assumptions. Actual usage changes with model, quality settings and activity. Leave room for growth and validate storage behavior after deployment instead of treating the estimate as a guaranteed day count.
Retention is different from evidence preservation
Routine recordings are eventually overwritten or deleted. Clips needed for an investigation should be flagged, exported, archived or placed into an appropriate case workflow before the routine window expires.
Redundancy changes usable capacity
Storage-protection choices can reduce usable capacity in exchange for resilience. The design should make that tradeoff explicit rather than quoting raw disk totals as usable recording space.
Review after installation
Confirm that every intended camera is recording, time is correct, expected days are accumulating, alerts work and authorized users can retrieve footage. Recheck after adding cameras or changing quality and retention settings.
Common questions
How many days will a drive retain?
There is no universal answer. It depends on camera models, quality, recording mode, activity and usable storage.
Is retention the same as a backup?
No. Routine retention is a rolling window. Important clips need a separate preservation or archive step.
Can older footage use less storage?
UniFi Protect supports retention controls, including enhanced-retention behavior on supported versions, but settings and consequences should be reviewed before use.
Primary references
Product features and interfaces change. Confirm current compatibility and documentation before designing or purchasing equipment.