Security camera calculator
A simple way to plan home cameras: one for each main entrance, one on each external corner (it watches the two walls that meet there), and a couple for the garden.
Your measurements
Result
- Points to cover
- 8 pcs
- Recommended cameras
- 9 pcs
An estimate from access points and corners; a site survey can reduce or increase the optimal number.
How the calculation works
- Points to cover = main entrances + external corners of the building + 2 for the garden, if included.
- Recommended cameras = points to cover + 10%, rounded up.
Worked example
A house with 2 entrances, 4 corners and a garden has 2 + 4 + 2 = 8 points to cover; with a 10% reserve, 9 cameras.
What the calculator assumes
- A camera on a corner watches the two sides of the house that meet there.
- Entrances (door, gate, garage) get a dedicated camera so faces are clearly visible.
When to adjust the result
- The field of view matters: a wide-angle camera can replace two, and a long garden may need one more.
- Cameras must not film the street or neighbouring property beyond what is necessary — data protection rules (such as the GDPR in the EU) apply at home too.
- Recording (card, NVR or cloud) and power (PoE, socket or battery) are chosen together with the cameras.
Placing cameras well — and legally
Cover entrances first: front and back doors, the gate and the driveway. Mount cameras at about 2.5–3 m, out of easy reach but low enough to see faces rather than the tops of heads, and avoid pointing them straight into the sun or bright lights.
Privacy rules matter. In many countries, including the UK and EU states, filming beyond your own property — the street, a neighbour's garden or windows — brings data-protection obligations or is not allowed. Aim cameras at your own land, use privacy masks where needed and put up a sign that recording is taking place.
Frequently asked questions
How many security cameras does a house need?
Typically one per entrance and one per external corner — often 6–10 for a detached house with a garden.
Can my camera film the street?
In the EU, only as far as strictly necessary for your property; point cameras at your own land.
Wired or wireless cameras?
Wired (PoE) cameras are more reliable and need no batteries; wireless ones are easier to install but depend on Wi-Fi strength and battery or power-supply placement.
How long should footage be kept?
Only as long as needed — often a few days to a month. Data-protection guidance in many countries discourages keeping recordings longer without a reason.