# Arch Calculator

The arch calculator calculates the distance between the *focus points* (F) and the
arch's center (C). This distance is calculated based on the arch's height and width.
Using the diagram below as a reference, the
arch's height is represented as distance (H). The arch's width is
represented as distance (K). Distance (E) is equal to distance (D). Points represented
as (F), represent the foci of the arch.

This calculator will not allow the height (H) to be greater than
1/2half the arch's width (K). However, the height (H) can be equal
to 1/2 of the width (K). The result is a perfect circle with a
radius of (H) and a diameter of (K).

For details on how to use these calculations to create the shape of the arch
and built it, refer to the
How to Build an
Archway section.

## Learn How to Use the Arch Calculator to Build an Arch

(click on the image below)

**Elliptical Point Measurements**

**What next?**

See other
**Carpentry Calculators** and **Math Formulas used in Carpentry**

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