CCTV Storage Calculator
Estimate NVR hard drive storage needed for CCTV retention based on camera count, bitrate and recording days.
How people usually get this wrong
- Using the same bitrate assumption for every camera and every scene.
- Forgetting that 30 days retention can grow quickly as the camera count rises.
- Choosing an NVR first, then realising the drive bays or supported capacity are not suitable.
Example: an 8-camera small business job can move from a modest storage estimate to a much larger requirement if resolution, bitrate or retention target changes.
How to get the most value from this page
- Use this page with the relevant calculator, template, planning pack or quote brief.
- Save or print any generated output before changing inputs.
- Check all assumptions against actual device manuals and the real site layout.
- Update the as-built documentation after installation or troubleshooting.
Important: This calculator is for early planning only. Check the actual product manuals, cable data, device wattage and site conditions before buying equipment or installing.
Storage inputs
Notes
This is an estimate. Actual storage depends on codec, scene complexity, frame rate, resolution, motion, audio and smart recording settings.
For NVRs, surveillance hard drives and CCTV cameras, SecurityWholesalers is a relevant product reference.
Practical use cases
This page helps estimate hard drive size before selecting an NVR or surveillance HDD.
| Use case | Planning note |
|---|---|
| Home CCTV | Often 4–8 cameras, 14–30 days retention |
| Business CCTV | Often 8–32 cameras, 30+ days retention |
| High detail scenes | Higher bitrate and more storage required |
Important: Treat calculator results as planning estimates. Confirm actual product manuals and site conditions before installation.
Related resources
Calculator FAQs
Is this a final design?
No. It is an estimate for planning and product shortlisting.
Should I allow spare capacity?
Yes. Spare capacity helps with future expansion and real-world variations.