CCTV Detection-Distance Calculator
How far out can a camera still detect that a person is there? Enter the resolution, lens and sensor to get the DORI detect distance (25 px/m — the loosest level, ideal for wide perimeter cover) alongside the tighter observe, recognise and identify ranges. Planning figures; real cameras vary. Runs in your browser.
- Observe (62 px/m — see clothing & behaviour)33.0 m
- Recognise (125 px/m — recognise a known person)16.4 m
- Identify (250 px/m — read a face or number plate)8.2 m
Planning estimate only — this is a geometric limit; light, motion, compression and lens quality all reduce real performance, and detection at range is only useful paired with motion or analytics. Verify with a site test. If a camera also views neighbours or public space, mind the DPDP Act 2023. Nothing is stored.
Turn detection range into a coverage plan
Related Guides — Deep-dive reading
CCTV Resolution Explained (India 2026): How Many Megapixels You Actually Need
What MP, 1080p, 2K, 4K and 8MP really mean, how pixels-per-metre and DORI decide whether you can recognise a face or read a number plate, and why 'enough' beats 'maximum' for Indian homes and shops.
SecurityCamera Field-of-View Schedule for India (2026): Proving Each Camera Sees What It Should
A ready-to-adapt professional schedule that records, per camera, the scene it must cover and to what purpose level - monitor, detect, recognise or identify - so coverage intent is stated at design and proven at commissioning.
SecurityCCTV Coverage Schedule for India (2026): Mapping Every Camera to a Purpose
A ready-to-adapt design-stage schedule that lists every zone to be covered, ties each one to a camera reference and a coverage purpose, and makes gaps and overlaps visible before you write the camera schedule and BOQ.
SecurityRelated Tools — You may also find these useful
CCTV Identification-Distance Calculator
How far a camera can still identify a face or number plate (DORI 250 px/m), from resolution, lens and sensor.
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Focal length, sensor and resolution to field-of-view angle, scene width and DORI detect/observe/recognise/identify distances.
Lens & FoVCCTV Recognition-Distance Calculator
How far a camera can still recognise a known person (DORI 125 px/m), from resolution, lens and sensor.
Recognise Distance