Security Camera Coverage Calculator
Estimate how many security cameras are needed to fully cover a given area based on camera field of view, mounting height, and overlap requirements.
Formulas Used
Ground depth of coverage (along tilt axis):
dfar = H × tan(T + FOVV/2)
dnear = H × tan(T − FOVV/2) [= 0 if angle ≤ 0°]
Coverage Depth = dfar − dnear
Ground width of coverage (horizontal):
dcenter = H × tan(T)
Coverage Width = 2 × dcenter × tan(FOVH/2)
Effective coverage per camera (accounting for overlap):
Effective Depth = Coverage Depth × (1 − Overlap/100)
Effective Width = Coverage Width × (1 − Overlap/100)
Number of cameras:
Cameras Along Length = ⌈Area Length / Effective Depth⌉
Cameras Along Width = ⌈Area Width / Effective Width⌉
Total Cameras = Cameras Along Length × Cameras Along Width
Where H = mounting height, T = tilt angle from vertical, FOVH = horizontal field of view, FOVV = vertical field of view.
Assumptions & References
- All cameras are assumed to be identical and mounted at the same height.
- The area is assumed to be flat (no elevation changes).
- Coverage depth is calculated along the camera's tilt axis; width is calculated perpendicular to it at the center distance.
- Overlap percentage reduces the effective (non-redundant) coverage footprint of each camera to ensure seamless coverage at boundaries.
- A tilt angle of 0° means the camera points straight down; increasing tilt angles point the camera toward the horizon.
- The combination of tilt angle and vertical FOV must not reach or exceed 90° (the horizon), as this would result in infinite ground projection.
- Typical security cameras have horizontal FOV of 60°–110° and vertical FOV of 40°–70°.
- Recommended overlap for reliable coverage is 15–25% (ASIS International, Physical Security Standards).
- Formula reference: Projective geometry of pinhole camera model; trigonometric ground projection (IPVM Camera Calculator methodology).