This Camera Focal Length Calculator finds the Lens Focal Length From a Field of View

Camera Lens Focal Length Calculator

A Camera Focal Length Calculator. This Calculates a Lens EFL for Cameras.
A Camera Focal Length Calculator. This Calculates a Lens EFL for Cameras.

This effective focal length calculator helps you select a lens to use with your camera. The calculator takes your target field of view (angle of view) and camera specification then provides the required lens EFL.

The calculator uses the camera lens focal length equation. This formula is different than the lens maker's equation which is intended for simple thin lens elements.

The Optical Effective Focal Length (EFL) should not be confused with the Mechanical Back-Focal Length (BFL). The EFL determines the field of view of the camera while the BFL determines whether a lens will focus on a camera.

Read Our Camera Calculator & Optics Design Page, or Click below Use our Other Camera Calculators

Camera Field of View Calculator. FoV Calculator
Camera Depth of Field Calculator. DoF Calculator.
Camera Angle of View Calculator for Camera Lens Selection. AoV Calculator.

Building a Camera? Use Our Wide-Angle Lens Calculator or Browse Below

Aerial Robotics?

Our light-weight, miniature lenses are ideal for collision avoidance, long-distance viewing, and end-customer viewing.

Fast 6mm M12 Lens

CIL061-F1.9-M12B650

6mm M12 Lens for Blackfly S-mount cameras
6mm M12 Lens for Blackfly S-mount cameras
6mm M12 Lens for FLIR Blackfly S and AR0234
6mm Lens for IMX290
$39.00

Low Distortion 2.7mm M12 Lens

CIL027-F2.8-M12A650

IMX226 Dart Camera 3mm M12 Lens
IMX226 Dart Camera 3mm M12 Lens
Mipi camera M12 Lens for S-Mount FLIR
Arducam IMX477 2.7mm M12 Lens
$39.00

200°@6.3mm Fisheye M12 Lens

CIL219-F2.5-M12IR

200° M12 Fisheye Lens
200° M12 Fisheye Lens
200° Mini Fisheye Lens
Mini M12 Fisheye Lens
$79.00

Surveillance?

Our low F#, high resolution lenses are suitable for 180° dome cameras, low light, and active IR illuminated scenes.

Wide-Angle 3.2mm CS Mount Lens

CIL032-F2.0-CSA650

A 3.2mm CS Mount Lens for a Wide Lens Security Camera
A 3.2mm CS Mount Lens for a Wide Lens Security Camera
The CommonLands CIL03.2-F1.8-CSNOIR 3.2mm EFL lens is pictured with the Raspberry Pi HQ Camera.
The CommonLands CIL03.2-F1.8-CSNOIR 3.2mm EFL lens is pictured next to the Raspberry Pi HQ Camera.
$79.00

Large Format 5.1mm M12 Lens

CIL050-F2.0-M12A650

Large Format 5.1mm M12 Lens
Large Format 5.1mm M12 Lens
5mm M12 Lens Allied Vision
5mm S Mount Lens for Computer Vision
$59.00

190°@9.1mm Fisheye M12 Lens

CIL231-F1.9-M12A650

3mm Mini Fisheye M12 Lens
3mm Mini Fisheye M12 Lens
3mm S Mount Fisheye Lens Raspberry Pi
Miniature Fisheye Lens
$99.00

Surveillance?

Our low F#, high resolution lenses are suitable for 180° dome cameras, low light, and active IR illuminated scenes.

Consumer / AR+VR?

Our high resolution fisheye lenses will let you design 360° cameras and and stereographic lenses are equivalent to "GoPro" lenses.

Video Conferencing?

Our wide-angle, low distortion, high resolution M12 lenses result in optimal object deformation without post-processing.

Video Conferencing?

Our wide-angle, low distortion, high resolution M12 lenses result in optimal object deformation without post-processing.

Mobile Robotics?

Find a low F# or low distortion lens to optimize your computer vision framerate.