Optics
Mirror Magnification
The ratio of image size to object size. Negative magnification indicates an inverted image.
Variables
Munitless
Magnification
dim
Image distance
dom
Object distance
him
Image height
hom
Object height
Your notes
0/5000
Check value
Round inputs run through this page's calculator. Use it to test your own working or a rearranged form. It is a test case, not a real-world example.
- di = 2 m (Image distance)
- do = 3 m (Object distance)
Result: M = -0.66666667
Other optics formulas with the same quantities
- Lens Magnification (Lenses) shares Magnification, Image distance, Object distance
- Thin Lens Equation (Lenses) shares Object distance, Image distance
Where this formula is listed
- Optics formulas, under Reflection, alongside Law of Reflection, Focal Length and Radius, Fresnel Reflection (Normal Incidence) and Spherical Mirror Focal Length.
- In the optics list it comes after Mirror Equation and before Focal Length and Radius.
- Optics formula sheet, one of 34 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the Mirror Magnification formula?
Mirror Magnification is written M = −d_i/d_o = h_i/h_o. The ratio of image size to object size. Negative magnification indicates an inverted image. It belongs to Optics, under Reflection.
What are the units in M = −d_i/d_o = h_i/h_o?
In SI units, M is magnification (dimensionless); d_i is image distance, measured in m; d_o is object distance, measured in m; h_i is image height, measured in m; h_o is object height, measured in m.