Updated · Built and checked by the PlinzoTools team, formulas tested against published sources
Calculate a parallelogram's area from its base and height.
18.0000
This tool calculates a parallelogram's area from its base length and the perpendicular height.
Enter the base and the height. The area appears instantly.
Area = base × height
A parallelogram can be turned into a rectangle without changing its area. Cut a right triangle off one slanted end and slide it to the other end, and the pieces fit together into a rectangle with the same base and the same perpendicular height. That is why the formula is identical to that of a rectangle, and why using the slanted side length instead of the true height gives the wrong answer. The tool multiplies your base by your height and displays the result to four decimal places, in square units of whatever unit you entered.
Imagine a hypothetical slanted flower bed shaped like a parallelogram. The long edge along the path is 8.4 meters, and the perpendicular distance from that edge to the opposite edge is 2.5 meters. Enter base 8.4 and height 2.5.
Area = 8.4 × 2.5 = 21 square meters
The bed covers 21 square meters. Its slanted sides might each be about 3 meters long, but those lengths play no part in the area.
Often you can measure both side lengths and one interior angle, but not the perpendicular height. In that case, height = slanted side × sin(angle between the slanted side and the base). For a hypothetical slanted side of 5 with a 30 degree angle to the base, the height is 5 × 0.5 = 2.5. Compute that first and enter it as the height. The tool does not take angles itself, so you should do this conversion separately.
You can pick either pair of parallel sides as the base, but the height must be the perpendicular distance to that same pair. If you use the long side as the base, the height is shorter; if you use the short side as the base, the height is longer. Both choices give the same area, so you can use this as a check on your measurements.
Parallelograms occur in tilted panels, patterned tiles, road markings, sloped garden beds, and geometry homework. For construction or landscaping quantities, treat the result as the ideal geometric area and add an allowance for waste based on your supplier or contractor guidance.
Yes -- a parallelogram's area formula is identical to a rectangle's, as long as "height" means the perpendicular distance between the two parallel bases, not the length of a slanted side.
Multiply the slanted side by the sine of the angle between it and the base. Enter the result as the height in the calculator.
Moving a triangular piece from one end of the parallelogram to the other turns it into a rectangle without changing the enclosed space.
Yes, as long as the height is measured perpendicular to that same pair. Both choices give the same area.
No. It returns only the area, because the perimeter would need the length of the slanted sides.
Reference: NIST Weights and Measures