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Parallelogram Area Calculator

The area of a parallelogram is its base times the height between the base and the side opposite: area = b × h. This page opens on the parallelogram shape rather than the rectangle, whatever shape you last used on the main area calculator, with base 10 and height 6 filled in on a first visit, so the stage already reads Parallelogram · b h and the working row underneath reads 10 × 6 = 60. The height is not the slanted side: it is the straight distance measured at a right angle to the base, and the drawing beside the answer marks it with a dashed line labelled with your own number. Base and height go in one unit together, millimetres, centimetres, metres, inches or feet, the area comes back in that unit squared, and the rows below list the same area in six more units, so a patio measured in feet still reads in square metres.

b = 10 cmh = 6 cm
Parallelogram · b h60cm²6,000 mm² · 0.006 m² · 9.30002 in²
Flat
Solid, surface area
Base (cm)
Height (cm)
Unit

The height is the straight distance between the base and the side opposite, not the slanted side.

  • The workingarea, in cm²
    10 × 6 = 60
  • Square millimetresmm²
    6,000
  • Square metresm²
    0.006
  • Square inchesin²
    9.30001860004
  • Square feetft²
    0.0645834625003
  • Square yardsyd²
    0.00717594027781
  • Acresac
    0.0000014826322888
The formula is on the stage, and the working is the first row. Every answer here is one textbook formula with your numbers put in, printed so you can check it: a circle is π r², a three-sided triangle is Heron's formula, a regular polygon is n s² / (4 tan(π/n)). The solids give surface area for a closed shape, both ends of a cylinder and the base of a cone included. Conversions use exact definitions, so a square foot is 0.09290304 m² and 43,560 of them make an acre.

Common questions

What is the formula for the area of a parallelogram?
Area = b × h, the base multiplied by the height at a right angle to it. The stage prints the formula beside the answer as Parallelogram · b h, and the first row underneath is that formula with your numbers in place, for example 10 × 6 = 60. Both measurements go in the same unit and the answer is in that unit squared, so 10 cm by 6 cm is 60 cm². The headline shows six significant figures and the rows below it twelve, so a whole answer like 60 prints as 60.
Which line is the height, and what happens if I use the slanted side?
The height is the straight distance from the base to the side opposite it, measured at a right angle, and the hint under the fields repeats that while you type. The drawing beside the answer marks it as a dashed line running from the base to the opposite side, labelled with the number you typed. A slanted side is always longer than that distance, so putting it in the height field gives an area that is too big: a parallelogram with a base of 8 and a side of 5 leaning at 50 degrees is 30.6418, not 40.
I know two sides and the angle between them. Can I use those?
Not directly. The fields here are base and height, and no shape on this page takes a pair of sides with the angle between them: the angle the Sector shape asks for is the angle at the centre of a circle. Turn your pair into a height first, with h = a × sin θ, where a is the slanted side and θ is the corner angle. A side of 5 at 50 degrees gives a height of 3.83022, and with a base of 8 the working row then reads 8 × 3.83022 = 30.64176. That is the a b sin θ formula, done in two steps.
Does it work for a rhombus or a diamond shape?
Yes. A rhombus is a parallelogram with four equal sides, so its area is still base times height: a side of 5 with a height of 4 to the side opposite prints 5 × 4 = 20. The other rhombus formula, half the product of the two diagonals, is not an input here. None of the shapes on this page takes a diagonal, so if the diagonals are what you measured, multiply them and halve the result yourself.
Why does a parallelogram have the same area as a rectangle with the same base and height?
Leaning the shape over moves area from one end to the other without changing how much of it there is: cut the triangle off one end, slide it to the other, and you have a rectangle b by h. The page lets you check that. Parallelogram with base 10 and height 6 gives 60; the Rectangle shape with length 10 and width 6 prints 10 × 6 = 60; the Trapezoid shape with both parallel sides 10 and a height of 6 prints ½ × (10 + 10) × 6 = 60.
How do I get a patio measured in feet as square metres?
Choose ft in the unit row before you type, and the two fields read Base (ft) and Height (ft) together. A base of 12 ft with a height of 8 ft is 96 ft², and the rows underneath give the same area as 8.91869184 m², 10.6666666667 yd² and 13,824 in². The conversions use exact definitions, so a square foot is exactly 0.09290304 square metres. For feet and inches, type the inches as a decimal: 8 ft 6 in goes in as 8.5.
Does it give the perimeter or the length of the slanted side?
No. This page computes area only, and the two numbers it asks for are the base and the height, so it never learns how long the slanted side is. The perimeter is 2 × (base + slanted side), an addition you can do once you have measured that side. Everything else on the page is the same area shown in another unit, and the Copy button beside each row copies that figure on its own.

Every area is computed from the formula shown, exact to the precision of the numbers you type, and conversions use exact unit definitions. Measurements from the real world carry their own error.