Compare calculators

Both calculators run independently — change the inputs on either side to compare results.

Focal Length Calculator

Find the focal length of a lens given the distance to the object and the distance to the formed image. Essential for photographers, opticians, and physics students working with thin-lens optics.

Object Distance (cm)

Image Distance (cm)

Fill in the required fields to see your result.

Optics

Magnification Calculator

Compute the optical magnification of a lens or mirror by comparing the image height to the object height. Use it to determine whether a lens enlarges, reduces, or inverts an object.

Image Height (cm)

Object Height (cm)

Fill in the required fields to see your result.

Key differences

	Focal Length Calculator	Magnification Calculator
Category	Optics	Optics
Inputs required	2	2
Result	Focal Length (cm)	Magnification (×)
What it does	Find the focal length of a lens given the distance to the object and the distance to the formed image. Essential for photographers, opticians, and physics students working with thin-lens optics.	Compute the optical magnification of a lens or mirror by comparing the image height to the object height. Use it to determine whether a lens enlarges, reduces, or inverts an object.