Use this feet and inch diagonal calculator to easily find the diagonal between two sides of any rectangle. This makes squaring up any lay out a snap.

# How to Square up a Lay Out

- Establish two parallel lines for the the width
- Establish a starting point for the length on one of the lines
- Mark the length down one of the lines from the starting point
- Mark the diagonal on the other line from the same starting point
- Mark the length down the line from the diagonal mark
- Check the width, the length and diagonal measurements to ensure everything is right