Camera FOV Calculator - Lens Field of View Calculator Free

How to Use the FOV Calculator

1. Select your sensor size — choose from common sizes: 1/3", 1/2.7", 1/2.5", or 1/1.8" — these match popular security camera models
2. Enter focal length — type the lens focal length in mm (typical range is 2.8mm to 12mm for security cameras)
3. Enter target distance — specify the distance from the camera to the area you need to cover, in meters or feet
4. View FOV results — instantly see horizontal field of view (degrees), vertical field of view (degrees), coverage width, and coverage height at the target distance
5. Experiment with settings — try different focal lengths and distances to see how coverage changes — higher focal length = narrower but more detailed view
6. Recommended lens — the calculator may suggest an optimal lens based on your desired coverage dimensions

Perfect for security system designers, CCTV installers, and surveillance professionals planning camera placement and lens selection.

Features

• Common sensor sizes — 1/3", 1/2.7", 1/2.5", 1/1.8" — the most widely used security camera sensor formats
• Focal length range — 2.0mm to 50mm covers everything from wide-angle to telephoto lenses
• Coverage area — width and height at a given target distance in meters or feet
• Horizontal & vertical FOV — both angles displayed for accurate placement planning
• Visual reference — coverage pattern visualization helps you understand the field shape
• Lens recommendations — suggests what focal length gives you the coverage you need
• Instant updates — recalculates as you change any parameter

Use Cases

• Security system design — determine whether a 2.8mm wide-angle lens or a 6mm narrow lens is right for each camera position
• Parking lot coverage — calculate how many cameras you need to cover a parking lot with no blind spots
• Entryway monitoring — check if your existing camera captures the full door area or if you need a wider lens
• License plate capture — for LPR (license plate recognition), you need a narrow FOV — calculate the right focal length for a specific distance
• Warehouse installation — plan ceiling-mounted camera placement to ensure aisles and racking are fully covered

FAQ

What sensor size should I select?

Check your camera’s specifications — the sensor size is usually listed as 1/3", 1/2.7", 1/2.5", or 1/1.8". If you’re unsure, 1/3" is the most common for security cameras and a safe default. Larger sensors (1/1.8") capture more light but may have a different FOV at the same focal length.

How does focal length affect what I see?

Shorter focal lengths (2.8mm) give a wider, panoramic view but less detail at a distance. Longer focal lengths (6mm, 12mm) zoom in on a narrower area but capture more detail of what’s in that area. For general surveillance, 2.8-4mm is common; for identification purposes, 6mm or higher is better.

What’s the difference between optical zoom and digital zoom?

Optical zoom changes the focal length physically using lens elements — it captures more detail. Digital zoom simply crops and enlarges the image, reducing quality. This calculator is for fixed-focal-length lenses and optical zoom settings. Digital zoom does not change the FOV.

How many cameras do I need for full coverage?

Divide the total area by the coverage width at your target distance, then add 20-30% overlap between cameras to avoid blind spots. For example, if each camera covers 40 ft wide and you need to cover 100 ft, plan for 3 cameras with overlap.

Can I use this for PTZ cameras?

Yes — for PTZ (pan-tilt-zoom) cameras, calculate for the zoomed-out (widest) position to see the full coverage area, then calculate for the zoomed-in position to see the identification zone. This helps you position the camera so both extremes are useful.