Trapezoid Perimeter Calculator
P = a + b + c + d. Sum of two parallel sides + two non-parallel.
Result
Perimeter
26.0000
Isosceles trapezoid; area = 32.0000.
- a (top)6
- b (bottom)10
- c (left)5
- d (right)5
- Perimeter26.000000
- Height4
- Area32.000000
- Isosceles?Yes
Step-by-step
- P = a + b + c + d = 6 + 10 + 5 + 5 = 26.0000.
- Area = ½(a + b) × h = 8.0000 × 4 = 32.0000.
How to use this calculator
- Enter the two parallel side lengths (a, b).
- Enter the two non-parallel sides (c, d).
- Enter height for area calculation.
About this calculator
A trapezoid has exactly one pair of parallel sides (US definition; UK calls it "trapezium"). Perimeter is the sum of all four sides. Area = ½(a + b)h where a and b are the parallel sides and h is the perpendicular height between them. Isosceles trapezoid (c = d) is symmetric — common in pediments, drink-can profiles, and bridge spans.
Frequently asked
US: "trapezoid" = one pair parallel; "trapezium" = no parallel sides. UK: opposite. Conventions vary; this calculator uses US.
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