Find the side length and area of a square inscribed in a circle.
Last updated: June 2026 | By Patchworkr Team
Enter a real number.
For an inscribed square, the diagonal equals the circle diameter, so the side is r sqrt(2).
1. Enter the circle radius.
2. Read the live side length and area for the inscribed square.
3. Check the area against the enclosing circle if needed.
For radius 5:
side = 5 sqrt(2) ≈ 7.0711
area = 2 * 5^2 = 50
Because the diagonal of the square equals the circle diameter and a square diagonal is side times sqrt(2).
Yes, for a square inscribed in a circle of radius r.
Yes, as long as it is a positive finite number.
Yes. All four vertices lie on the circle.
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