When to use: Use this tool when sizing the NVR/VMS storage array and network for a surveillance system. It estimates per-camera bitrate, total storage for a target retention period, the aggregate recording bandwidth the NIC and switch must carry, and compares H.264 vs H.265 vs H.265+ so you can quantify storage savings. Bitrate estimates are approximate — scene complexity and motion dominate real-world usage, so always verify against your camera or VMS bitrate calculator.
At 8 TB surveillance-rated drives, the 6.22 TB target needs about 1 data drive, or 2 drives with one parity drive (RAID 5). Add a hot spare for critical systems and round up to the next array size.
This tool sizes NVR and VMS storage arrays for IP camera systems by calculating per-camera bitrate, aggregate recording bandwidth, and total storage across multiple codec options. It is used for final storage specification including RAID drive configuration and codec comparison.
Per-camera bitrate is calculated from a resolution-based reference bitrate scaled by the fps/30 ratio and a codec compression factor relative to H.264 baseline. Audio, if enabled, adds 64 kbps. Total storage is: GB per camera per day = bitrate (Mbps) × 86,400 s × duty_cycle / 8 / 1,000 (decimal GB); total GB = GB/cam/day × cameras × retention days; total TB = total GB / 1,000.
The duty cycle represents the fraction of time cameras are recording. Continuous 24/7 is 100%. Motion-triggered recording at typical commercial scenes is approximately 30–40%. The margin field adds RAID parity overhead and headroom — 20% covers RAID 5 parity on a 5-drive array and filesystem overhead.
Codec comparison calculates the same storage requirement under H.264, H.265, and H.265+ simultaneously, so engineers can quantify the storage savings from codec upgrade.
Video retention requirements are set by the AHJ, owner security policy, and applicable regulations. HIPAA Security Rule requires healthcare video to be retained per facility policy (commonly 90 days). Government facilities may require 180 days or more. Airport TSA security plans specify their own retention. Financial industry FINRA rules require audit trail retention. The storage sizing tool enables engineers to meet any retention requirement once the bitrate parameters are determined.
H.265 and H.265+ deliver substantial storage reductions, but require both cameras and the VMS to support the codec. Confirm VMS server CPU capacity to decode H.265 streams — H.265 decoding is approximately 1.5–2× more CPU-intensive than H.264. For large systems, H.265 savings may offset the need for more powerful VMS servers.
For RAID arrays, specify surveillance-rated drives rated for continuous write duty. The drive configuration suggestion (data drives + parity drive for RAID 5) uses 8 TB as the reference drive size — adjust in your specification based on actual drive size availability. Add a hot spare drive for production systems to allow automatic array rebuild after a drive failure.
Enter camera count, frame rate, resolution, and codec. Select the recording mode (continuous or motion-triggered) and enter the duty cycle if using motion. Enter retention days and the RAID/headroom margin. The results panel shows per-camera bitrate, aggregate bandwidth, raw storage, and storage with margin. The codec comparison table shows H.264, H.265, and H.265+ storage side by side. The drive configuration panel recommends a minimum number of 8 TB data drives and a RAID 5 parity configuration.
For RAID 5, add one drive worth of overhead (approximately 20–25% for a 4–5 drive array). In the tool, enter 20% as the margin. This covers the parity drive, filesystem overhead, and leaves a small buffer for unplanned retention extensions. For RAID 6 (two parity drives), add 33–40% margin on a 4–5 drive array.
A 4K (8MP) camera at H.265, 15 fps, continuous: approximately 6 Mbps per camera × 86400 × 1.0 / 8 / 1000 = 64.8 GB/day × 90 days = 5,832 GB = 5.83 TB per camera. A 32-camera 4K system at 90 days continuous would require approximately 186 TB raw before margin.
H.265+ is a proprietary smart codec from manufacturers such as Hikvision and Dahua that uses background scene modeling to eliminate redundant encoding of static image areas. It achieves 60–70% bitrate reduction vs H.264 on static scenes (corridors, parking areas) but provides less savings on high-motion scenes. It is not an IEEE standard and requires cameras and NVR from the same manufacturer.
Audio adds approximately 64 kbps (0.064 Mbps) per camera when enabled. For a 30-camera system, audio adds only 1.92 Mbps — negligible compared to video. However, audio recording has legal restrictions in many jurisdictions (two-party consent laws). Confirm legal requirements before enabling audio recording.
The NVR NIC and switch uplink must carry the full aggregate bitrate from all cameras simultaneously during recording. Size the NIC and switch uplink above the calculated aggregate Mbps — a 1 GbE link handles up to approximately 700–800 Mbps sustained. Use 10 GbE for systems with aggregate recording bandwidth above 500 Mbps.
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