Macro Reproduction Ratio
Find the magnification ratio of a subject image on the sensor.
About Macro Reproduction Ratio
A reproduction ratio compares the image size on the sensor to the real subject, so 0.5 means the subject appears at half its real size. Lenses marketed as macro reach at least 1x, and the ratio tells you the smallest subject that fills the frame.
Formula
Macro Reproduction Ratio
Magnification = sensor width / subject width
- magnification
- 1.0 means life size on the sensor
Worked example
With the default values below, Macro Reproduction Ratio returns Magnification of 0.40. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Sensor widthminimum 1
- 36
- Subject widthminimum 1
- 90
Results
- Magnification
- 0.40 x
- Ratio
- 0.4 : 1
- Subject Scale
- 40.00%
Step by step
- 1Values used
- 2Macro Reproduction Ratio
- 3Magnification= 0.40 x
- 4Ratio= 0.4 : 1
- 5Subject Scale= 40.00
Assumptions and limits
- The result is derived only from the 2 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Macro Reproduction Ratio calculated?
Magnification = sensor width / subject width A reproduction ratio compares the image size on the sensor to the real subject, so 0.5 means the subject appears at half its real size.
Why does Macro Reproduction Ratio matter?
Lenses marketed as macro reach at least 1x, and the ratio tells you the smallest subject that fills the frame.
What values do I need to enter?
This calculator takes 2 inputs: Sensor width, Subject width. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.