Area Calculator for Regular and Irregular Polygon Shapes

Calculate the area of any shape you draw, or image you trace regardless of scale or complexity.

SketchAndCalc™ is both a web application accessible from and iOS mobile app used to calculate the area and perimeter of both regular and irregular polygon shapes.

Tracing over imported images or Google maps allows users to calculate the square areas and perimeters of floor plans, building plots, or parcels of land. Importing an image to trace over extends it's usefulness to landscape gardeners, building contractors, surveyors or home improvement enthusiasts who have a digital image to work from.

Simply import the image onto the drawing canvas and begin tracing the schematic, plan or irregular shape until the polygon is closed. At which point the application accurately returns the perimeter and area of the shape in both imperial (IP) measurements; square inches (sq in) square feet (sq ft) square yards (sq yd) square miles (sq mi). As well as metric (SI) measurements; square centimeters (sq cm), square meters (sq m), square kilometers (sq km). Professionals who wish to save and share calculations for later editing can do so.

The drawing canvas scale can be adjusted to accommodate very large areas such as the floorplan 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.

Area Calculator for iPhone, iPad, and iPod

The mobile Area Calculator of the same name, designed for the iPhone, iPad and iPod is available for download from the website and Apple's iTunes Store.

Functionality between the browser app and the mobile app is similar, with the exception of drawing gestures which must be adapted to a touch screen interface. However, both apps present line lengths as you draw to ensure the shapes scale matches that of the object to be calculated.

The SketchAndCalc mobile App for iOS also supports importation of .PDF image files to trace over. PDF files that contain multiple pages require an image browser to allow the user to select the page before importing.

Features Include: 

• Select a drawing scale in feet, inches, meters or centimeters 
• Import .JPG .GIF and multipage .PDF's
• Snap to grid On / Off
• Edit lengths with numeric keypad
• Edit vertex with double tap
• Re-establish vertex with double tap
• Dropbox integration
• Undo last line / vertex move
• Pinch to Zoom in / out
• Shake to clear canvas
• Panning the canvas
• Save calculations to file system for later editing or review
• Share a calculations image and XY coordinates via email 
• Display a table of saved calculations XY coordinates
• Delete saved calculations 
• Snap to grid On / Off
• Edit line lengths with Numeric keypad
• Pinch to Zoom In / Out

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How to calculate an Area

So your searching the internet for an easy way to calculate the area of a triangle, or perhaps you need a volume calculator. With SketchAndCalc™ you simply draw the desired shape and the area is displayed. If a volume calculator is needed simply multiple the surface area by the shapes depth to arrive at the total volume.

How to calculate Area

To calculate the area of regular shapes or polygons such as a triangle is simple. However shapes with irregular length sides or the area of a circle requires complex calculations.

Volume calculator

Calculating the volume of an object can be achieved using SketchAndCalc™ by calculating the surface area and multiplying it by the objects depth.

How to calculate the area

Shapes with equal sides can easily by calculated manually. However, a calculator is often needed for complex irregular areas.

How do you calculate area

The best calculation method depends on the area to be calculated. If you want to calculate the area of a regular shape use the applicable formula. However calculating an area of an odd shape would require an area calculator.

How do i calculate area

If speed and accuracy are important I recommend using SketchAndCalc™ to calculate the area of any regular or irregular shape.

Calculate the area

Of regular, or irregular polygons by drawing the shapes lengths on the canvas using SketchAndCalc™. The square area and perimeter result will be returned when the shape is closed.

Calculate an area

Whatever the scale or complexity, simply draw the area on the canvas and SketchAndCalc™ will calculate the perimeter and square area.

Area triangle

Is perhaps the easiest of shapes to calculate using SketchAndCalc™. Simply draw the triangle and collect the square area.


Area = a2
a = length of side


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


Area = b�h
b = breadth
h = height


Area = b�h
b = breadth
h = height

Trapezoid (US)
Trapezium (UK)

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


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


Area = ?ab


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.