Magnification Calculator
Works out how much bigger or smaller an image is than the object.
Magnification
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Share sends a link that reopens these numbers. Copy details pastes the full breakdown as a list.
Image height —
Image —
The formula
m = hᵢ ÷ h₀ = −dᵢ ÷ d₀
A negative figure means the image is upside down. The size of the figure says how much bigger or smaller it is. This is the magnification of one lens or mirror, not the angular magnification quoted for telescopes.
What to watch out for
For a real lens system, multiply the magnification of each stage.
Frequently Asked Questions
What is the magnification with an object at 30 cm and an image at 60 cm?
-2: twice the size and inverted.
What does a magnification of 0.5 mean?
An upright image half the size of the object.