How Accurate is our Area Calculator?

So you’ve trialed SketchAndCalc™, but just how accurate is our area calculator?

Area of Regular Polygon Shapes
Based on the number of vertices (control points), and the angles between them, SketchAndCalc™ automatically detects whether a Square, Rectangle or Circle is present.

For these regular polygons, a formula is chosen to calculate area based on the length of the perimeter sides (or circle diameter). How Accurate is our Area Calculator? It’s accurate to 10,000 decimal places.

Area of Irregular Polygon Shapes
Shapes with sides of any length and interior angles of any measure use the polygon method of calculation, also known as the ‘Shoelace, or Surveyor’s formula’.

Given the nature of drawing or tracing shapes on a screen, the more faithfully a shape is traced, or described, the more accurate the results.

Our area calculator is as accurate as how well the shape is described.

Therefore, area result inaccuracy can be greatly reduced by adjusting the canvas zoom level, drawing slowly, and using a high-resolution image (if tracing over an image).

One important note to consider when tracing an area over an image or photograph is whether the horizontal and vertical dimensions of the imported image are a true 1:1 ratio. Images can sometimes be scaled in one dimension, making any attempt to calculate its true area impossible.

SketchAndCalc™ also has many drawing techniques that can be used to improve the accuracy of drawing irregular areas.

Such as:

Manually enter a line length

Improve accuracy by manually entering a line length?

Fine adjust the position of a vertex

How accurate is our area calculator? Improve accuracy by fine adjusting the position of a vertex?

Delete a stray vertex

How accurate is our area calculator? Improve accuracy by deleting stray vertices.

Add a vertex to better describe the perimeter

How accurate is our area calculator? Improve accuracy by adding a vertex?

Draw fixed angles

How accurate is our area calculator? Improve accuracy by using the constrained line tool

Draw circular shapes

How accurate is our area calculator? Use the circle tool to draw bezier curves.

Draw with a stylus (Mobile app)

Consider using a drawing stylus to improve accuracy on our mobile app.

Draw curves slowly

Draw slowly using the curved line tool for the most accurate area results.

With irregular area calculations, rounding up line lengths is required to avoid unnecessarily large arrays of numbers that would detrimentally impact performance when working with 10,000 decimal places.

So, how accurate is our area calculator? Tests have shown this rounding results is a negligible variance of 0.002%.