Engineering Calculation

CCTV Camera Storage Capacity Calculation

Nov 2026

Direct Answer

CCTV storage capacity is estimated from the number of cameras, average bitrate and recording retention period with an engineering reserve. In this example, the recommended preliminary storage capacity is 94.92 TB. Final sizing should be verified using OEM bitrate data and VMS requirements.

At a Glance

Resource ID	EC-076
Number of Cameras	N \| 64 \| Nos.
Average Bitrate per Camera	B \| 4 \| Mbps
Retention Period	T \| 30 \| Days
Engineering Margin	M \| 20 \| %
Source detail	Refer to Technical Content
Source detail	Refer to Technical Content
Source detail	Refer to Technical Content

Calculation Method & Worked Example

Storage (GB) = (Total Bitrate × 86400 × Retention Days) ÷ (8 × 1024)

Recommended Storage = Calculated Storage × (1 + Margin)

Total Bitrate = 64 × 4 = 256 Mbps

Calculated Storage = 79.10 TB

Recommended Storage = 79.10 × 1.20 = 94.92 TB

Preliminary calculation based on source inputs and assumptions.

Applicable Standards Listed in the Source

IEC 62676	Video surveillance systems
ONVIF	Interoperability
ISO/IEC 27001	Information security
OEM Documentation	Camera bitrate specifications

Technical Content

1. Purpose

To estimate the storage capacity required for CCTV recordings based on camera quantity, bitrate and retention period.

2. Engineering Objective

To determine the preliminary storage requirement for NVR/VMS sizing. Final sizing shall be verified using camera OEM bitrate data, codec settings and project recording requirements.

3. Applicable Standards

Standards are listed above as supplied in the source document.

4. Design Inputs

Number of Cameras = N = 64 = Nos.; Average Bitrate per Camera = B = 4 = Mbps; Retention Period = T = 30 = Days; Engineering Margin = M = 20 = %

5. Assumptions

Continuous recording, constant average bitrate and H.264/H.265 compression as configured. RAID overhead is excluded.

6. Formula(s)

Storage (GB) = (Total Bitrate × 86400 × Retention Days) ÷ (8 × 1024)
Recommended Storage = Calculated Storage × (1 + Margin)

Calculated Storage: 79.10 TB
Recommended Storage Capacity: 94.92 TB

7. Variables Explained

N = Cameras; B = Bitrate per camera; T = Retention period; M = Engineering margin.

8. Step-by-Step Calculation

Total Bitrate = 64 × 4 = 256 Mbps
Calculated Storage = 79.10 TB
Recommended Storage = 79.10 × 1.20 = 94.92 TB

Calculated Storage: 79.10 TB
Recommended Storage Capacity: 94.92 TB

9. Worked Engineering Example

A CCTV system with 64 cameras recording continuously at 4 Mbps for 30 days requires approximately 94.92 TB of storage including a 20% engineering reserve.

10. Engineering Output

Calculated Storage: 79.10 TB
Recommended Storage Capacity: 94.92 TB

11. Design Considerations

Verify codec, frame rate, resolution, motion recording, RAID level, redundancy and future expansion.

12. Common Design Mistakes

Ignoring bitrate variations, RAID overhead, retention requirements and future camera additions.

13. Practical Site Notes

Monitor storage utilization regularly and configure automatic overwrite policies where permitted.

14. Limitations

This is a preliminary engineering calculation only. Final storage shall be confirmed using OEM bitrate calculators and VMS requirements.

15. Related Engineering Systems

CCTV Cameras, NVR, VMS Server, Network Switches, Storage Arrays.

16. Cross References

Related FAQ: CCTV Storage Sizing
Related White Paper: WP-006
Related Case Study: CS-006
Related Engineering Diagram: ED-076

Related White Paper: as referenced in the source document.

Related Case Study: as referenced in the source document.

Related Engineering Diagram: as referenced in the source document.

17. SEO Meta Title

CCTV Camera Storage Capacity Calculation | EC-076

18. SEO Meta Description

Engineering calculation for estimating CCTV camera recording storage capacity.

19. URL Slug

ec-076-cctv-camera-storage-capacity-calculation

20. Keywords (15)

CCTV Storage,NVR Storage,IEC62676,ONVIF,Video Storage,Engineering Calculation,Camera Bitrate,VMS,Surveillance,Retention,Storage Capacity,Security Systems,NVR,CCTV Design,Recording

21. AI Search Summary

Frequently Asked Questions

How is the preliminary detector quantity calculated?

What is the result for this example?

A CCTV system with 64 cameras recording continuously at 4 Mbps for 30 days requires approximately 94.92 TB of storage including a 20% engineering reserve.

Does this establish the final detector layout?

This is a preliminary engineering calculation only. Final storage shall be confirmed using OEM bitrate calculators and VMS requirements.

What design factors should be checked?

Verify codec, frame rate, resolution, motion recording, RAID level, redundancy and future expansion.

SEO & Publishing Details

SEO meta title	CCTV Camera Storage Capacity Calculation \| EC-076
Meta description	Engineering calculation for estimating CCTV camera recording storage capacity.
Primary keyword	CCTV Storage
Secondary keywords	NVR Storage; IEC62676; ONVIF; Video Storage; Engineering Calculation; Camera Bitrate
Suggested URL slug	ec-076-cctv-camera-storage-capacity-calculation
Suggested image alt text	CCTV Camera Storage Capacity Calculation, Engineering Calculation EC-076.

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