Calculate how much storage your security camera system needs. Enter the number of cameras, average bitrate, recording schedule and retention period to estimate your NVR or NAS storage requirement.
How much storage do security cameras need?
Security camera storage depends primarily on the number of cameras, their average bitrate, how many hours per day they record and how long you want to retain footage.
Resolution alone does not determine storage usage. Two 4K cameras can use very different amounts of storage depending on compression, frame rate, image complexity and bitrate settings.
Typical security camera bitrates
| Resolution | Typical bitrate | Approx. storage per camera/day |
|---|---|---|
| 1080p | 2 Mbps | 21.6 GB |
| 2K / 4MP | 4 Mbps | 43.2 GB |
| 5MP | 6 Mbps | 64.8 GB |
| 4K / 8MP | 8 Mbps | 86.4 GB |
| High-quality 4K | 12 Mbps | 129.6 GB |
These figures assume continuous 24-hour recording at the stated average bitrate. Motion-only recording can substantially reduce storage consumption.
H.264 vs H.265 storage
H.265 can generally deliver similar image quality at a lower bitrate than H.264, but the real difference depends on the camera, scene, firmware and encoding configuration.
For the most accurate estimate, check the bitrate configured on your camera or NVR and enter that value directly into the calculator.
Should you add a storage reserve?
Yes. Camera bitrate is rarely perfectly constant. Busy scenes, night-time noise, firmware changes and higher frame rates can increase storage consumption. A reserve of around 10–20% is a practical starting point when planning an NVR or NAS.
Continuous vs motion recording
Continuous recording provides predictable retention but requires much more storage. Motion or event-based recording can dramatically reduce storage requirements, although actual savings depend on how frequently motion occurs.
Frequently asked questions
How much storage do 8 4K security cameras need for 30 days?
At an average bitrate of 8 Mbps per camera and continuous 24/7 recording, eight cameras require about 20.74 TB of raw storage for 30 days. Adding a 15% reserve increases the estimate to approximately 23.85 TB.
Is 8 TB enough for security cameras?
It depends on camera count, bitrate and retention period. For example, a small system using lower bitrates or motion recording may fit easily within 8 TB, while several continuously recording 4K cameras may require considerably more.
Does motion recording use less storage?
Usually yes. Instead of storing video continuously, the recorder saves footage only when an event is detected. The actual reduction depends on how active the monitored area is.
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