Geometry
Rectangle Perimeter Calculator
Add the lengths of all four edges.
Let’s calculate.
PopularitySee what you’re calculating
Add the lengths of all four edges.
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THE IDEA, SIMPLY
How it works
Add the lengths of all four edges.
FORMULA
Perimeter = 2 × (width + height)
A worked example
A 5 m by 3 m rectangle has perimeter 16 m.
Formula & detailed explanation
Both lengths nonnegative and expressed in the same unit.
Calculations use decimal arithmetic with 40 significant digits internally. Choose 0–8 decimal places for the displayed result. Trailing zeros are omitted. Rounding affects only the displayed and copied result; very small values may round to zero. Accepted inputs have up to 100 characters and magnitudes from 10⁻¹⁰⁰ to 10¹⁰⁰, plus zero.