Fill in either the side length or the area, then click Calculate. The tool uses Area = side × side to compute the missing value and diagonal = side × √2 to give you the diagonal length.
This calculator is based on the square area formula: Area = side × side. Knowing either the side length or the area lets you solve for the other.
If you know the side a, then Area = a × a. If you know the area S, side = √S. After the main result is found, the tool also gives the diagonal using d = a × √2.
Square area and diagonal calculations are common in floor plans, drawings, construction, packaging design and many other scenarios. This calculator helps you perform these conversions quickly.
Make sure all values are greater than 0 and use consistent units (for example, all in meters, centimeters or millimeters) so the computed area and diagonal remain meaningful.
Area = side × side.
Area = 4 × 4 = 16 m².
Side = √25 = 5 m.
Diagonal = side × √2.
The diagonal is about 1.414 times the side length (√2 × side).
Mixed units lead to meaningless results; consistent units ensure the area and diagonal reflect real size.
Not directly. First compute side = diagonal ÷ √2, then you can obtain the area.
Yes. Both side and area fields accept decimal values for precise calculations.
Students, teachers, engineers, designers and anyone who needs square area and diagonal conversions.
Side length represents a physical dimension and must be positive; negative values have no geometric meaning.
This tool lets you enter either the side length or the area of a square to find the other value and also shows the corresponding diagonal length. Useful for learning, design and everyday geometry calculations.
Scan the QR code to use this tool on mobile.