By Zencalcy Editorial TeamLast reviewed About us
Magnification compares the image size with the object size. Mirrors and lenses produce a transverse magnification equal to minus the image distance over the object distance, so a negative result means the image is upside down.
Image size and orientation from distances or heights.
m = −d_i / d_o = h_i / h_o
m is the transverse magnification, d_i and d_o the image and object distances, and h_i and h_o the image and object heights. The negative sign in the distance form marks inversion.
| Symbol | Meaning |
|---|---|
| m | Transverse magnification, dimensionless. |
| d_i, d_o | Image and object distances from the optical element. |
| h_i, h_o | Image and object heights. |
m = −1 / 0.5 = −2. The image is twice as tall as the object and inverted, which is typical of a real image formed by a converging lens.
Continue with the Magnifying Glass Calculator, Malus's Law Calculator, or the Microscope Magnification Calculator — or browse more optics and light tools and all physics calculators.
It means the image is inverted relative to the object. For a single lens or mirror this usually goes with a real image.
Results are computed from the standard equations of classical mechanics. Unit conversions use the SI definitions published by NIST. Air resistance is ignored unless the calculator names a drag model.
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Last reviewed: September 2026. See how we build and check every tool on the about page.
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Content updated: September 2026