Enter the total amount of rainfall (in) and the total amount of evaporation (in) into the Effective Rainfall Calculator. The calculator will evaluate the Effective Rainfall.

## Effective Rainfall Formula

The following two example problems outline the steps and information needed to calculate the Effective Rainfall.

ER = RF - E

Variables:

- ER is the Effective Rainfall (in)
- RF is the total amount of rainfall (in)
- E is the total amount of evaporation (in)

To calculate the effective rainfall, subtract the evaporation amount from the total rainfall.

## How to Calculate Effective Rainfall?

The following steps outline how to calculate the Effective Rainfall.

- First, determine the total amount of rainfall (in).
- Next, determine the total amount of evaporation (in).
- Next, gather the formula from above = ER = RF - E.
- Finally, calculate the Effective Rainfall.
- After inserting the variables and calculating the result, check your answer with the calculator above.

**Example Problem : **

Use the following variables as an example problem to test your knowledge.

total amount of rainfall (in) = 1.25

total amount of evaporation (in) = .30

ER = RF - E** **= ?