Compare calculators

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

Thin Lens Focal Length Calculator

Compute the focal length of a thin lens from object and image distances, or find where an image forms for a known lens. Essential for optics lab work, camera design, and eyeglass prescription analysis.

Object Distance (cm)

Image Distance (cm)

Fill in the required fields to see your result.

Optics

Depth of Field Calculator

Compute the total depth of field for any camera and lens combination using focal length, f-number, focus distance, and circle of confusion. Use it to plan sharp focus zones before a shoot.

Focal Length (mm)

F-Number

Focus Distance (mm)

Circle of Confusion (mm)

Fill in the required fields to see your result.

Key differences

	Thin Lens Focal Length Calculator	Depth of Field Calculator
Category	Optics	Optics
Inputs required	2	4
Result	Focal Length (cm)	Depth of Field (mm)
What it does	Compute the focal length of a thin lens from object and image distances, or find where an image forms for a known lens. Essential for optics lab work, camera design, and eyeglass prescription analysis.	Compute the total depth of field for any camera and lens combination using focal length, f-number, focus distance, and circle of confusion. Use it to plan sharp focus zones before a shoot.