How to Select Hard Drives for NVR Recorders
Created on：2026-06-04 11:16
Core rule: Calculate daily storage per camera → Total cameras × retention days = Required capacity for hard drive selection
Bitrate standard: H.265 (mainstream encoding for modern NVR); H.264 consumes double storage space
1. Daily Storage Consumption per Camera (H.265, standard image quality)
表格
| Resolution | Recommended Bitrate | Daily Storage (GB/Day) |
|---|---|---|
| 2MP (1080P) | 2 Mbps | 21.6 GB |
| 4MP | 4 Mbps | 43.2 GB |
| 5MP | 5 Mbps | 54.0 GB |
| 8MP (4K) | 8 Mbps | 86.4 GB |
Storage Formula
Daily Capacity(GB)=Bitrate(Mbps)×3600×24÷8÷1024Example for 4Mbps: 4×3600×24÷8÷1024≈43.2GB
2. Practical Calculation Examples (30-day recording, most common requirement)
- Example 1: 4×4MP cameras, store 30 daysTotal=4×43.2×30=5184GB≈5.1TB → Select 6TB surveillance HDD
- Example 2: 8×8MP cameras, store 30 daysTotal=8×86.4×30=20736GB≈20.2TB2-bay NVR: 2pcs ×10TB; 4-bay NVR:4pcs×6TB
- Example 3:16×2MP cameras, store 30 daysTotal=16×21.6×30=10368GB≈10.2TBSingle-bay:12TB; Dual-bay:2pcs×6TB
Note for H.264 older devices
H.264 coding needs twice the storage space of H.265.e.g. 2MP H.264 ≈43.2GB per day
3. Hard Drive Purchase Guidelines
- Use Surveillance-grade Hard Disk only continuous operation.
- Actual usable capacity: Marked 1TB ≈931GB, reserve extra 5% spare space in calculation.
- RAID backup: Double total capacity for critical sites (shops, factories).
- Custom storage days: Multiply total capacity by 3 if 90-day retention needed.
4. Quick Reference (Per camera for 30-day recording)
- 2MP: ≈0.65TB per channel
- 4MP: ≈1.30TB per channel
- 5MP: ≈1.62TB per channel
- 8MP: ≈2.59TB per channel
