Disk space to record your cameras for X days.
Fields contain editable examples.
Four cameras at 4 Mbps recording 24 hours a day produce 172.8 GB per day: about 5.2 TB for 30 days. The example assumes a constant average bitrate and excludes NVR formatting and RAID.
Constant average bitrate per camera. With motion detection, enter the hours with actual activity. Decimal GB and TB; excludes NVR formatting and RAID.
GB/day = cameras × Mbps × 3600 × hours / 8000; TB = GB/day × days / 1000Constant average bitrate per camera. With motion detection, enter the hours with actual activity. Decimal GB and TB; excludes NVR formatting and RAID.
All amounts use the same currency of your choice. These are estimates, not measurements or offers.
Size the hard drive of an NVR or video recorder before you buy it. Enter the average bitrate of each camera, shown in its video settings. Typical H.265 values: 1080p between 1 and 2 Mbps, 4 MP between 2 and 4 Mbps and 4K between 4 and 8 Mbps. H.264 often needs almost twice as much.
Choose a drive with headroom: the NVR reserves space and overwrites the oldest footage when full. A 6 TB drive covers this example with some margin; with RAID 1 in the recorder you need two. If you record on motion only, real usage can be much lower.
In the camera or NVR video settings, next to resolution, codec and frames per second. Use the average value, not the maximum.
At similar quality it usually cuts bitrate by 30% to 50%, depending on the scene and manufacturer. Measure your own setup.
Enter the real hours of activity per day. If there is motion for about 6 hours a day, use 6 instead of 24.