CCTV Storage & Bandwidth Calculator
Add your camera groups, choose retention and RAID, and get bandwidth, storage and the number of hard drives for your NVR.
Estimates use typical bitrates for medium scene activity, daytime. Night IR, rain, trees and busy scenes raise bitrate. Disk capacity is shown as usable (about 0.91 TB per marketed TB). If you know your camera's actual bitrate, enter it in "Custom bitrate". Always confirm final designs with the NVR maker's calculator. Calculator by Techubox.com.
How to use the CCTV Storage Calculator
This free CCTV storage calculator tells you how many terabytes your NVR needs, how much network bandwidth the cameras use, and how many hard disks to order. It handles mixed camera groups, so you can enter 4MP domes, 8MP bullets and PTZs in one project and get a single total.
Step by step
- Add a camera group and enter the number of cameras, resolution, codec (H.264 or H.265) and frame rate.
- Set the bitrate, or keep the suggested value for that resolution and codec.
- Choose the recording mode (continuous or motion) and how many hours a day you record.
- Enter the retention period in days, for example 30 days.
- Pick a RAID level and disk size to see usable capacity and the number of disks.
Worked example
16 cameras at 4MP H.265, each streaming about 4 Mbps, recording 24/7 for 30 days: total bandwidth is 64 Mbps, which is about 0.69 TB per day and about 20.7 TB for 30 days, before RAID overhead.
Frequently asked questions
How much storage do I need for 16 cameras for 30 days?
It depends mainly on bitrate. At 4 Mbps per camera (typical 4MP H.265), 16 cameras need about 20.7 TB for 30 days of continuous recording. Motion recording can cut this by half or more.
Does H.265 really save storage?
Yes. H.265 usually needs 30 to 50% less bitrate than H.264 for the same picture quality, so storage drops by about the same amount. Smart codecs (H.265+) can save more on quiet scenes.
Should I add a safety margin?
Yes. Add 10 to 20% for bitrate spikes at night and in busy scenes, and remember RAID 5 or RAID 6 takes one or two disks for parity.
Is the result in TB or TiB?
The calculator uses decimal terabytes (1 TB = 1000 GB), the same way disk makers label drives.