Example 1
- Base: 8
- Height: 5
40.00
a = 8 and h = 5 gives 40.00.
Parallelogram area calculator
Type the base and the height perpendicular to it. The calculator multiplies a by h and shows area in cm² or in², matching the unit switch.
A = a × h. A rectangle is on the rectangle area calculator. A rhombus is on the rhombus area calculator.
Result
Base a (cm) and Height h (cm). Area shows up here.
How it works
Parallelogram area is the base times the height that drops perpendicular to that base. The first card example, 8 and 5, is 40.00.
At a right angle the same pair is an 8 by 5 rectangle, also 40, because then h is the other side. A triangle 8 and 5 has only 20.00, half of this figure.
A low strip 15 and 2 gives 30.00. A square pair 7 and 7 gives 49.00. Order does not invent an angle: 6 and 8 is 48.00, the same as 12 and 4. That is still a times h, not a b sin α. You do not type an angle in this calculator.
The calculator does not run when the base or the height is missing. A slanted side is not h.
Switching to inches relabels the result as in² and does not convert a typed 8. A rhombus from diagonals e f / 2 is on the neighbouring page: 6 and 8 on that page is 24, another formula.
If you know a slanted side and an angle, measure height or open the sine page. Pythagoras does not stand in for h. At 10 and 6 you get 60.00, the same as a 10 by 6 rectangle when the height really is 6.
How to use
- Type base a, the edge the height drops onto, in cm or inches.
- Type height h perpendicular to that base, not the length of the neighboring side.
- Click Calculate. The result uses two decimal places and cm² or in².
- Do not type an angle. Sine a b α lives on another page, not here.
- The 8 and 5 example is 40.00. That is not 20 from a triangle ½ah and not 24 from a rhombus with diagonals 6 and 8.
Formula
A = a × h
Not a b sin α.
A = a × h at 8 and 5
Base times perpendicular height. a = 8 and h = 5 give 40.00. a = 10 and h = 6 give 60.00. Not a b sin α.
- A
- Area a × h. 8 × 5 = 40.00. 12 × 4 = 48.00. 7 × 7 = 49.00.
- a
- Base. 8 with h = 5 is 40. 10 with h = 6 is 60.
- h
- Height perpendicular to a. 5 with a = 8. A slanted side does not enter this formula.
Examples
Example 2
- Base: 10
- Height: 6
60.00
a = 10 and h = 6 gives 60.00.
Example 3
- Base: 12
- Height: 4
48.00
a = 12 and h = 4 gives 48.00.
Example 4
- Base: 7
- Height: 7
49.00
a = 7 and h = 7 gives 49.00.
Example 5
- Base: 15
- Height: 2
30.00
a = 15 and h = 2 gives 30.00.
Example 6
- Base: 9
- Height: 3
27.00
a = 9 and h = 3 gives 27.00.
Example 7
- Base: 6
- Height: 8
48.00
a = 6 and h = 8 gives 48.00.
Example 8
- Base: 11
- Height: 5
55.00
a = 11 and h = 5 gives 55.00.
Frequently asked questions
Is this a b sin α?
No. Here you type base and height. Angle and a second side live on the sine page. 8 and 5 give 40.00 without a sine.
Why do 8 and 5 give 40, same as an 8 by 5 rectangle?
At a right angle the height is the other side. The parallelogram still uses a h. A rectangle is the special case.
Is rhombus e f / 2 here?
No. The diagonal rhombus has its own card. You do not type e or f here. 6 and 8 on the rhombus is 24, another formula.
What if I leave h empty?
Nothing is computed. Type height or load 8 and 5. Empty h does not become a segment of area a.
Is a triangle 8 and 5 the same 40?
Half of eight times five is 20. The parallelogram is 40. Half versus whole, two cards.
Can I mix centimeters and inches?
Not in one run. Both dimensions in cm or both in inches. The switch changes the label and does not convert numbers.
Can I type a slanted side as h?
No. h is perpendicular. A slanted side is longer and spoils 40.00.
Why do 15 and 2 give 30.00?
To show a low parallelogram. The product 30 is legal. The formula does not need a close to h.
Does trapezoid ½(a+b)h replace this area?
No. A trapezoid has two bases. Here one base and h. 8 and 5 here is 40; a trapezoid still needs b.
Is 10 and 6 equal to 60.00?
Yes. Same as a 10 by 6 rectangle when h really is 6. At 11 and 5 you get 55.00.
Knowledge sources
The calculator computes the same formula as the definition below.
Page updated in 2026.