Enter the water line length (ft), the beam (ft), and the draft (ft) into the Wetted Surface Area Calculator. The calculator will evaluate the Wetted Surface Area.

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## Wetted Surface Area Formula

The following formula is used to calculate the Wetted Surface Area.

WSA = WLL * (B+D)

Variables:

- WSA is the Wetted Surface Area (ft^2)
- WLL is the water line length (ft)
- B is the beam (ft)
- D is the draft (ft)

To calculate the wetted surface area, multiply the water line length by the sum of the beam and draft.

## How to Calculate Wetted Surface Area?

The following steps outline how to calculate the Wetted Surface Area.

- First, determine the water line length (ft).
- Next, determine the beam (ft).
- Next, determine the draft (ft).
- Next, gather the formula from above = WSA = WLL * (B+D).
- Finally, calculate the Wetted Surface Area.
- 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.

water line length (ft) = 20

beam (ft) = 10

draft (ft) = 5

WSA = WLL * (B+D) =** ** ?