Free Irregular Polygon Area Calculator

Sketch And Calc Calculates the Area and Perimeter of any Regular or Irregular Shape you Draw.

The area and perimeter results are displayed when the shape is closed. The scale can be adjusted to accommodate very large areas such as the floor plan of a building, or the square meters area of a kitchen work surface.

Using your cursor, draw the shape of any object. Line lengths are displayed below the cursor to ensure measurements are accurate. And they can be adjusted after the shape is complete. The area and perimeter results are then displayed.

In addition to being able to add / delete new vertices, and change the scale, the tool offers a Sharing feature. This allows users to save the calculation as an URL to paste into an email or blog. Thus supporting users wishing to collaborate on the calculation with others.

If your browser is unable to view the area perimeter calculator, you should download the Adobe Flash plug-in here. Alternatively use the area formula below:

Square

Area = a2
a = length of side

Triangle

Area = 1 b?h
b = base
h = vertical height

Rectangle

Area = b?h
b = breadth
h = height

Parallelogram

Area = b?h
b = breadth
h = height

Trapezoid (US)
Trapezium (UK)

Area = 1(a+b)h
h = vertical height

Circle

Area = ?r2
Circumference = 2?r
r = radius

Ellipse

Area = ?ab

Sector

Area = 1r2?
r = radius
? = angle in radians

Here are some common terms used when calculating area:

A - Area
C - Circumference
L - Length
W - Width
H - Height
r - Radius
d - Diameter
Pi - 3.14 constant (p)
S - Surface Area

Understanding how to calculate area is important to understand at the early age of 8-10. Calculating area is a pre-algebra skill that should be well understood prior to beginning algebra. Students need to understand the early concepts of calculating the area of a variety of shapes. And using our irregular polygon area perimeter calculator is no substitute for this knowledge.

Units for measuring area

We measure area using squares. We use different sizes of squares depending on how big or small an area is.
Example Lengths of sides of Squares might be:

Size of a draftsmans pencil- Millimeter / Millimetre mm2
Size of piece of paper - Centimeter / Centimetre cm2
Size of a roll of carpet - Meter m2
Size of a parcel of land - Kilometer / Kilometre km2

We write square sizes using a small 2 next to the unit.
We write mm2, cm2, m2 , km2, cm2
We can say "63 millimeters / millimetres squared" or " 63 square millimeters / millimetres"

We could use small squares to measure large areas. The only problem with this is that we would end up having to use very big numbers. For example, a field might be measured at 5,000,000,000 square millimetres / millimetres when 5,000 square meters would be a much easier size to say, write, and visualise / visualize.

You will probably hear more units for measuring area; square inches, square feet, square yards, square miles, acres, hectares are all units used for measuring area.

How did Sketch And Calc come to be?

The drawing component of sketchandcalc.com was created for Home Energy Calc www.homeenergycalc.com. Home Energy Calc is another calculator created for users wishing to calculate the thermal efficiency of their home, to describe the home envelope. Thus outputting the heat energy in British Thermal Units, or indeed in Kilowatt hours that infiltrate (gain) or escape (loss) the home. HVAC equipment can then be sized accurately for an individual home and climate.

Similar to homeenergycalc.com, homeheathero.com performs a simular calculation for the HVAC professional, but uses a default home envelope to provide a basic estimate. Thus homeheathero does not use this area calculation tool you see here.