How much recording storage do you actually need?
Retention is a decision, not a default. The right number is longer than the time it typically takes you to find out something happened, which for most businesses is longer than they think.
About this estimator
- Free, no email required
- Shows its working and its assumptions
- Nothing leaves your browser
- Updated 2026-08-24
Storage is decided by four things: how many cameras, at what resolution, at what frame rate, held for how long. Change any one and the number moves a lot.
The output below also reports the sustained upload bandwidth those same cameras would need if you recorded to the cloud instead. That figure usually decides the local-versus-cloud question, and almost nobody presents it.
Your estimate
Usable storage
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Sustained cloud upload
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What is behind the number
Estimates in Canadian dollars before tax, for comparing quotes and spotting a gap. A real number comes from someone walking the building.
Why 30 days is the number most people land on, and when it is wrong
Thirty days is the common default because it covers a month-end discovery cycle: somebody notices stock is short, or a customer disputes something, and there is still footage. Seven days only works if you would reliably notice inside a week.
Where longer is worth paying for: sites with infrequent visits, seasonal operations, anywhere a dispute might surface months later, and anywhere an insurer or a contract specifies a period. Where shorter is fine: a small office with somebody in it every day.
Usable is not the same as advertised
The figure above already carries 20 percent headroom, for two reasons. A recorder writing to a nearly full array behaves badly, and bitrates spike in bad weather when everything in frame is moving. Buy the next size up rather than the exact number.
One more thing that is not storage but is the same conversation: a single large disk is a single point of failure, and disks that write continuously fail within a few years. Two or more in a redundant set means one failure does not lose the footage. Whether that matters depends on what the footage is worth, which is its own subject.
Want a real number instead of a range?
An estimate is enough to decide whether to start. A quote needs somebody to look at the building. Ours are fixed scope and fixed price, agreed before any work begins.
Before you call
Why is my installer's number different from this?
Because real cameras vary considerably by model and settings, and this uses estimated bitrates. Use this to sanity-check a quote, then ask the installer for the actual bitrate of the specific camera model proposed. If they cannot tell you, that is informative.
Should I use motion recording to save space?
Sometimes. The catch is that motion percentages are unpredictable: a camera facing a road, a tree or a busy yard records nearly continuously whatever the setting says. If the view is active, size for continuous and treat any saving as a bonus.
Is 4K worth it?
Only if the pixels land on something. A 4K camera covering a whole parking lot has very few pixels on any individual face, and a 1080p camera framed properly on the door beats it for identification. Halving the frame rate roughly halves storage and makes almost no practical difference.