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

Camera Lens Effective 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.

Here are a Few M12 Lenses. Search all 50+ Using Our M12 Lens Calculator

Low Distortion 2.6mm M12 Lens

CIL028-F2.3-M12A650

Low Distortion 2.6mm M12 Lens

190°@9.1mm Fisheye M12 Lens

CIL231-F1.9-M12A650

190°@9.1mm Fisheye M12 Lens

Wide-Angle 3.5mm M12 Lens

CIL335-F3.6-M12ANIR

Wide-Angle 3.5mm M12 Lens

Small 3.3mm M12 Lens CIL036

CIL036-F2.2-M12A650

Small 3.3mm M12 Lens CIL036

No Distortion 3.9mm M12 Lens

CIL039-F2.8-M12A650

No Distortion 3.9mm M12 Lens

We Also have Cost Effective 12MP+ C-Mount Lenses for Machine Vision and Factory Automation.

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
CIL061-F1.9-M12B650
Fast 6mm M12 Lens
$39.00
3mm Wide Angle M12 Lens IMX415
3mm Wide Angle M12 Lens IMX415
Sony IMX415 Lens
M12 S Mount Lens for IMX415
CIL327-F1.5-M12A660
Wide-Angle 2.7mm M12 Lens
$39.00
Wide Angle M12 Lens
Wide Angle M12 Lens
Wide Angle S-Mount Lens
AR0820 M12 Lens
CIL344-F1.9-M12B660
Wide-Angle 4.5mm M12 Lens CIL344
$49.00
A 7mm M12 Lens
A 7mm M12 Lens
7mm M12 Lenses
7mm S Mount Lens
CIL872-F2.8-M12A650
Low Distortion 7.2mm M12 Lens
$29.00
Stereographic M12 Lens
Stereographic M12 Lens
Stereographic M12 Lens
Stereographic M12 Lens
CIL825-F2.4-M12ANIR
Small 2.5mm M12 Lens
$39.00
2mm M12 Lens stereographic
2mm M12 Lens stereographic
2mm M12 Lenses stereographic
2mm M12 lens F2
CIL819-F2.0-M08A650
Small 1.9mm M8/M12 Lens
$39.00

What's Your Application? Our Lenses Cover the Spectrum.

Wide-Angle 3.5mm M12 Lens

CIL335-F3.6-M12ANIR

Wide-Angle 3.5mm M12 Lens

Low Distortion 7.8mm M12 Lens CIL078

CIL078-F2.0-M12A650

Low Distortion 7.8mm M12 Lens CIL078

Mobile Robotics?

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

Factory Machine Vision?

Our cost-effective compact C-Mount lenses are designed for up to 1.1"~1.2" format global shutter sensors.

Low Distortion 6mm M12 Lens

CIL059-F1.7-M12BNIR

Low Distortion 6mm M12 Lens

GoPro 3.0mm M12 Lens

CIL331-F2.5-M12B650

GoPro 3.0mm M12 Lens

Intelligent Everywhere?

Our low distortion lenses with multiple F# can be used to optimize your depth of field.

Surveillance?

Our fisheye and IR Corrected lenses are suitable for doorbell cameras and active IR illuminated scenes.

195°@4.7mm Fisheye M12 Lens CIL216

CIL216-F2.2-M12A650

195°@4.7mm Fisheye M12 Lens CIL216

Fisheye 2.5mm CS Mount Lens

CIL725-F1.8-CSANIR

Fisheye 2.5mm CS Mount Lens

Wide-Angle 2.8mm M12 Lens CIL329

CIL329-F2.0-M12A650

Wide-Angle 2.8mm M12 Lens CIL329

Wide-Angle 3.6mm Lens

CIL336-F1.9-M12A650

Wide-Angle 3.6mm Lens

Does it Require Getting Dirty?

Our IP67 and IP69K lenses are suitable for applications exposed to the environment.

Aerial Robotics?

Our tiny lenses are ideal for collision avoidance and object recognition.

200°@6.3mm Fisheye M12 Lens

CIL219-F2.5-M12A650

200°@6.3mm Fisheye M12 Lens

Low Distortion 7.2mm M12 Lens

CIL872-F2.8-M12A650

Low Distortion 7.2mm M12 Lens