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

Wide-Angle 2.7mm M12 Lens

CIL327-F1.5-M12A660

Wide-Angle 2.7mm M12 Lens

Wide-Angle 4.5mm M12 Lens CIL344

CIL344-F1.9-M12B660

Wide-Angle 4.5mm M12 Lens CIL344

Low Distortion 7.2mm M12 Lens

CIL872-F2.8-M12A650

Low Distortion 7.2mm M12 Lens

Small 2.5mm M12 Lens

CIL825-F2.4-M12ANIR

Small 2.5mm M12 Lens

Small 1.9mm M8/M12 Lens

CIL819-F2.0-M08A650

Small 1.9mm M8/M12 Lens

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

4mm IP6K9K M12 Lenses
4mm IP6K9K M12 Lenses
4mm IP69 S Mount Lenses
4mm IP6K9K M12 Lens AR0230
CIL336-F1.9-M12A650
Wide-Angle 3.6mm Lens
$39.00
IP69 AR0234 Lens CIl329
IP69 AR0234 Lens CIl329
Small M12 AR0230 Camera Lens
AR0233 Wide Angle M12 Lens
CIL329-F2.0-M12A650
Wide-Angle 2.8mm M12 Lens CIL329
$39.00
Tiny M12 Fisheye Lens
Tiny M12 Fisheye Lens
Tiny S-Mount Fisheye Lenses
Tiny Fisheye Lens
CIL208-F2.2-M12A650
200°@2.9mm Fisheye M12 Lens
$49.00
1mm M12 Lens Stereographic Fisheye Lens
1mm M12 Lens Stereographic Fisheye Lens
1mm Tailored Distortion Lens
Tailored Distortion M12 Lens Fisheye
CIL207-F1.9-M12A650
220°@4.0mm Stereographic M12 Fisheye
$39.00
IMX462 M12 Lens CIL079
IMX462 M12 Lens CIL079
8mm M12 Lens CIL079
8mm S Mount Lenses CIL079
CIL079-F2.0-M12A650
Ingress Protected 7.8mm M12 Lens
$39.00
IR Corrected Day Night Fisheye Lens S-Mount
IR Corrected Day Night Fisheye Lens S-Mount
Surveillance Fisheye Lens S-Mount
Security Camera Fisheye Lens Day and Night
CIL239-F2.0-M12A650
186°@5.2mm IR Corrected Fisheye M12 Lens
$59.00

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

200°@4.5mm MiniFisheye M12 Lens

CIL914-F2.4-M12B650

200°@4.5mm MiniFisheye M12 Lens

200°@5.8mm Fisheye Lens

CIL273-F2.0-M12A650

200°@5.8mm Fisheye Lens

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.

IR Corrected 4.4mm M12 Lens CIL046

CIL046-F2.0-M12A650

IR Corrected 4.4mm M12 Lens CIL046

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.

185°@7.8mm Fisheye M12 Lens

CIL227-F2.5-M12B660

185°@7.8mm Fisheye M12 Lens

Small 2.1mm M12 Lens

CIL821-F2.4-M12ANIR

Small 2.1mm M12 Lens

190°@6.8mm Fisheye M12 Lens

CIL282-F1.8-M12B660

190°@6.8mm Fisheye M12 Lens

185°@7.8mm Fisheye M12 Lens

CIL227-F2.5-M12B660

185°@7.8mm Fisheye M12 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.

Small 1.9mm M8/M12 Lens

CIL819-F2.0-M08A650

Small 1.9mm M8/M12 Lens

Telephoto 50mm M12 Lens

CIL051-F2.8-M12ANIR

Telephoto 50mm M12 Lens