CCTV Storage Calculator Guide for Kenyan Businesses

Most CCTV quotes in Kenya either wildly over-size storage (charging for a 4TB drive when 1TB would do) or under-size it (leaving a business with three days of footage when they expected thirty). The actual formula isn't complicated -- it just isn't explained clearly. Here it is, plus a calculator you can use directly.

The formula

CCTV storage comes down to four numbers: how many cameras, how much data each one produces per second (bitrate), how many hours per day they record, and how many days you want to keep the footage.

Storage (GB) = (Bitrate in Mbps ÷ 8) × 3600 × 24 × Retention Days × Number of Cameras ÷ 1024

Bitrate depends on resolution, compression and how much motion is in the scene -- a busy loading bay uses more data than a quiet corridor at the same resolution. As a working estimate: a 2MP camera on H.265 typically runs 2-3 Mbps, a 4MP camera 3-5 Mbps, and an 8MP camera 6-10 Mbps.

Try it yourself

Practical sizing table

For a quick estimate without doing the maths, here's roughly what different setups need at 4MP resolution with H.265 compression and 24-hour recording:

Cameras	14-day retention	30-day retention	60-day retention
4	~0.7 TB	~1.5 TB	~3 TB
8	~1.4 TB	~3 TB	~6 TB
16	~2.8 TB	~6 TB	~12 TB

These are estimates for continuous recording -- motion-triggered recording or lower-motion scenes can reduce actual usage, sometimes significantly.

What actually changes the number

• Resolution -- doubling resolution roughly doubles bitrate at the same compression.
• Compression (H.264 vs H.265) -- H.265 typically halves file size versus H.264 at similar quality.
• Motion-triggered vs continuous recording -- a camera pointed at a quiet corridor with motion-only recording can use a fraction of the storage of 24/7 continuous recording.
• Frame rate -- lower frame rate (e.g. 15fps instead of 25fps) on low-activity cameras reduces storage with minimal loss of useful footage.

Qyvea sizes the actual NVR/DVR storage during the site survey based on your real camera count, resolution choice and desired retention -- this calculator is here so you know roughly what to expect before that conversation.