Kerova

Calculator · CCTV · Storage

CCTV storage and bandwidth calculator

Enter the number of cameras, the bitrate of each, the hours recorded each day and how many days you keep the footage. You get the disk space needed and the load on the network. The bitrate is your own figure, from the camera or the recorder's settings.

Your figures

cameras
Enter the bitrate in
Mbps

From the camera or recorder settings. It changes with the scene and the codec.

hours

24 for continuous recording.

days

Your retention period.

Overhead (optional)
%

Leave blank for none.

Result

Enter the cameras, bitrate and days to see the result.

Working

GB per day = Mbps × 3600 × hours ÷ 8 ÷ 1000

  • Network load = cameras × bitrate per camera.
  • Storage per camera per day in gigabytes = megabits per second × 3600 × hours ÷ 8 ÷ 1000.
  • Sizes are decimal (1 TB = 1000 GB), the way drive makers count. Computers often show binary sizes, which look a little smaller, so the tool shows that figure too. Some recorder software counts in binary units, which shows about 7% less per gigabyte.
  • There is no legal retention period. The ICO and the Surveillance Camera Code of Practice both say to keep footage no longer than you need for your stated purpose.
  • Overhead is optional. Use it to leave room for file system and recorder use. Leave it blank if you are unsure.

Storage sizes differ from how a drive shows up on a computer, and recorders keep some space for themselves. Add a margin, and check the recorder's own calculator for the final figure.

For guidance only. Always check against the current edition of the standard and the manufacturer's data.

Built by the engineer behind Kerova, certificate software for fire and security firms.