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Mirror Equation Calculator

Calculate image distance, magnification, and image characteristics for concave and convex mirrors using the mirror equation 1/s + 1/s' = 1/f.

Input
Mirror Parameters
Focal length (f)
f = R / 2
100.00mm
Radius of curvature (R)
Input value (with sign)
200.00mm
Image Formation
Image distance (s')
Positive → image in front of mirror (real)
150.00mm
Lateral magnification (m)
m = −s'/s
-0.50000
Image height (h')
h' = m × h
-5.0000mm
Image Characteristics
Image type
Real
Orientation
Inverted
Size
Diminished
Description
Real, Inverted, Diminished
Abridged Optics — Mirror Equation Calculator v1.0Uses the paraxial mirror equation 1/s + 1/s' = 1/f with standard sign conventions: positive distances are in front of the mirror (real), negative distances are behind (virtual). For convex mirrors, R and f are internally negated.

All information, equations, and calculations have been compiled and verified to the best of our ability. For mission-critical applications, we recommend independent verification of all values. If you find an error, please let us know.