Telescope Magnification Calculator
Free calculate telescope power, magnification, and eyepiece focal length. determine magnification using m = fₒ/fₑ for refracting and reflecting telescopes.
Input Parameters
Results
Enter focal lengths to calculate magnification
Telescope Magnification Formula
Magnification
M = fₒ / fₑ
Where:
- • M = magnification
- • fₒ = objective focal length
- • fₑ = eyepiece focal length
Typical Magnifications
- • Low power: 20-50×
- • Medium power: 50-150×
- • High power: 150-300×
- • Maximum useful: ~2× aperture (mm)