Find out how much hard drive space your cameras need.
Tell us about your cameras and how long you want to keep footage. The calculator works out how much hard drive space you need and how many days each drive will record, then suggests a WD Purple and a Toshiba drive that fit.
Work out your storage
1. Your cameras
How many
Camera resolution
Bitrate (optional)
2. How they record
Not sure? Choose H.265.
Busy scenes need more space.
25 is the UK standard. Lower means less space.
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Space needed for 30 days
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Used each day
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Total bitrate. Check your recorder can take this much.
Drives that fit
All results are estimates based on Hikvision's recommended settings. Real results depend on your cameras, settings and scene.
How it works
Each camera sends a stream of video to the recorder. The size of that stream is its bitrate, measured in Mbps. The calculator starts from the bitrates Hikvision recommends for H.265 at 25 frames per second:
2MP: about 2 Mbps
4MP: about 4 Mbps
5MP: about 4.6 Mbps
8MP: about 8 Mbps
3MP, 6MP and 12MP are estimated in proportion. The calculator then adjusts for your settings:
H.264 needs about twice as much space as H.265. Hikvision's figures and the video standard itself both say so.
H.265+: Hikvision says it cuts storage by up to 50% in most scenes and averages about a third of H.265. We use half for busy scenes and a third for quiet ones.
Busy scenes get 25% more. Hikvision advises raising the bitrate by 20–30% for complex scenes.
Motion-only recording uses the share of the day you pick. How much a camera actually records depends on your site, so treat this as a guide.
1 Mbps recorded for a whole day uses about 10.8 GB. Sizes are shown the way drive makers label them (1TB = 1,000GB).
Drive suggestions only include drives we stock. Camera ratings come from WD's and Toshiba's own datasheets. Also check the biggest drive your recorder accepts: some HiLook recorders take up to 8TB per drive.
Questions
Does 1TB really give 30 days on an 8MP camera?
It can, with H.265+ switched on and a quiet scene. Hikvision says H.265+ uses about a third of the space of H.265 on average, which gives an 8MP camera roughly 35 days on 1TB. Recording all the time in plain H.265, the same camera fills 1TB in about 11 days. On a busy scene such as a road it will be lower.
How accurate is this calculator?
It gives a good estimate based on Hikvision's recommended bitrates. Real results depend on the scene, lighting and camera settings. For the closest answer, enter your camera's own bitrate, and choose a drive with some room to spare.
Where do I find my camera's bitrate?
In the camera's web page, go to Configuration, then Video/Audio, then Video, and look at Max. Bitrate for the main stream. It is shown in Kbps. Divide by 1,000 to get Mbps, so 4096 Kbps is about 4 Mbps.
What happens when the hard drive is full?
With overwrite switched on, the recorder deletes the oldest footage to make room and keeps recording, so you always keep the most recent days.
What if I need more space than one drive?
Choose a recorder with two or more drive bays. The recorder uses the space on all its drives together. The calculator shows how many drives you would need.
Why does my recorder show less space than the drive size?
Drive makers and recorders count storage in slightly different ways, so a 4TB drive shows as about 3.6TB. It is the same amount of space. This calculator uses the drive makers' sizes.
See every drive side by side on our CCTV hard drives page. You can also browse NVRs and DVRs, or call our Wolverhampton trade counter on 01902 902251.
