6TB & 8TB Hard Drives (HDD) for CCTV & NVR
8TB and 6TB hard drives for 8–16 camera systems, 4K (8MP) cameras, or sites that need longer retention. The range covers WD Purple and Seagate SkyHawk surveillance drives, plus a Seagate IronWolf NAS drive for network storage. Use the guide below to size your system.
How many TB do I need for CCTV?
Storage depends on how many cameras you run, their resolution and bitrate, and whether you record 24/7 or only on events. A quick rule: GB per day ≈ bitrate in Mbps × 10.8 per camera. The table gives approximate retention for continuous recording at typical H.265 main-stream bitrates. Event or AI-triggered recording and H.265+ / Smart Codec usually stretch these figures well beyond the table.
| System (24/7 continuous, H.265) | 6 TB drive | 8 TB drive |
|---|---|---|
| 4 × 4MP cameras (~4 Mbps each) | ≈ 34 days | ≈ 46 days |
| 8 × 4MP cameras (~4 Mbps each) | ≈ 17 days | ≈ 23 days |
| 4 × 8MP / 4K cameras (~8 Mbps each) | ≈ 17 days | ≈ 23 days |
| 8 × 8MP / 4K cameras (~8 Mbps each) | ≈ 8 days | ≈ 11 days |
Estimates only. Actual retention depends on scene activity, frame rate, codec settings and the formatted capacity of the drive.
FAQ
How many days does an 8TB hard drive record?
On an 8-camera 4MP system recording 24/7 at about 4 Mbps per camera, 8TB holds roughly 3 weeks of footage. An 8-camera 4K (8MP) system at about 8 Mbps gives around 11–12 days. Event recording extends this.
Surveillance drive or NAS drive for an NVR?
For a CCTV recorder, choose a surveillance drive (WD Purple or Seagate SkyHawk), which is built for continuous video writing. NAS drives such as Seagate IronWolf are designed for network storage and file servers.
Do I need a surveillance hard drive, or will a desktop drive do?
Use a surveillance-rated drive such as WD Purple or Seagate SkyHawk in an NVR or DVR. They are built for the constant write load of 24/7 recording. Desktop drives are designed for lighter, intermittent use and are a common cause of recorder faults in the field.
Will this drive fit my NVR?
These are standard 3.5-inch SATA drives, which suit most Hikvision, Dahua and HiLook NVRs and DVRs. Before you buy, check two things on your recorder's datasheet: the maximum capacity it supports per SATA bay, and how many bays it has.
How do I get more days of footage?
Record on motion/AI events instead of 24/7, use H.265+ or Smart Codec, lower the frame rate (12–15 fps is plenty for most sites), or step up to the next drive size. Most recorders overwrite the oldest footage automatically when the drive is full.
Do you sell to installers and trade?
Yes. VIRTUS ELECTRONICS is an Australian online store. Trade customers can apply for a trade account, and you can request a quote for larger or multi-site orders.
Why Buy from Virtus Electronics?
We design, install, and supply genuine security systems and CCTV products in Australia. Every security product we stock has been tested and used by our team. We source only authentic security equipment from authorised Australian distributors, each backed by full manufacturer warranty. In-stock orders dispatch within 1 business day of payment being confirmed, and tracking details are emailed on dispatch. Professional installers and security integrators can apply for a Trade Account.
