Which input can I provide to get area, side or diagonal?

You can start from the side, the diagonal, the perimeter or the area. The tool applies square formulas to return the remaining measures and prepares the conversions in seconds.

How is the area converted to cm², m², in² or ft²?

Choose the base unit (m, cm, mm, in or ft) and the calculator normalizes the value before displaying the area in every available unit, including the squared version of your choice.

Is the diagonal obtained with the Pythagorean theorem?

Yes. It uses the relation d = s·√2 and its inverse s = d/√2 to compute the side even if you only know the diagonal.

How precise are the results?

The “Decimals” field lets you pick between 0 and 10 digits. All values are rounded to the same precision level to avoid inconsistencies.

Square area calculator

Q: Are decimals accepted and can I copy the results?

Yes. You can type numbers with comma or dot and then use “Copy results” to grab a complete summary of sides, perimeter, diagonal and converted areas.

Compute square area, perimeter, diagonal or side from any given value, with units and formulas.

Square area

Compute square area, perimeter, and diagonal starting from a single known value.

Input data

Method

Side (s) Diagonal (d) Perimeter (P) Area (A)

Value e.g. 5.75

Accepts comma or dot as decimal separator.

Units

Main area is shown in unit².

Decimals 0–10

Controls rounding for all outputs.

Aspect ratio

A square always keeps equal sides.

Results

Main area

Enter your data and press Calculate

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Side (s)

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Diagonal (d = s·√2)

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Perimeter (P = 4s)

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Area (A = s²)

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Area conversions

mm²

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cm²

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m²

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in²

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ft²

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Includes every calculated value.

Formulas used

Area from side: A = s²
Diagonal from side: d = s·√2
Perimeter from side: P = 4s
Side from area: s = √A

Which input can I start from?

You can start from the side, diagonal, perimeter, or area. The tool applies square formulas to return every other magnitude and prepares all conversions instantly.

How do area conversions to cm², m², in², or ft² work?

Select the base unit (m, cm, mm, in, or ft) and the calculator normalizes the value before showing the area in every available unit, including the squared version of your selection.

Is the diagonal calculated with the Pythagorean theorem?

Yes. It relies on d = s·√2 and its inverse s = d/√2 to obtain the side even when you only know the diagonal.

What precision do the results use?

The “Decimals” field lets you choose between 0 and 10 digits. Every output is rounded with the same precision to avoid discrepancies.

Can I enter decimals and copy the results?

Yes. You can type numbers with a comma or a dot and then use “Copy results” to grab a complete summary of sides, perimeter, diagonal, and converted areas.