Isometric Drawing Rules

Isometric drawing is one way of creating 3D pictures in 2D. While 3D drawing has been around for centuries, it was William Farish who first provided rules for isometric projection in 1822. Since then, isometric drawings have been used in everything from industrial design to instructions for flat pack furniture – in fact, anywhere it is important to show measurements and how things fit together. The method is also used by graphic designers and illustrators to create pictorial images. This infographic illustrates the three basic rules for creating an isometric drawing: firstly, horizontal lines are drawn at 30 degrees, with vertical lines staying vertical; secondly, the lines of each face are always drawn at an angle of 120 degrees; and thirdly, parallel lines remain parallel on three faces.

Click on the infographic to enlarge it.

isometric drawing rules infographic

Isometric drawing

William Farish (1759–1837), a professor at the University of Cambridge, developed criteria for isometric projection as he recognised the need for accurate technical drawings to explain mechanical principles and machinery. Farish published the technique he developed for isometric drawing in a paper in 1822.

Isometric drawing can be used to convey information in attractive and engaging graphics, and can make complex information more accessible and appealing to an audience than might be possible with a 2D illustration. It is an especially useful technique to show how something works and is commonly used in the design of products, interiors and infographics. Isometric drawings are also used for creating illustrative graphics to communicate information, for example, to create process diagrams, floor plans and instructions.

Isometric drawing rules

The term ‘isometric’ comes from Greek and means ‘equal measures’, as the projection uses fixed angles, and the height, width and depth are all to the same scale. The basic rules for isometric drawing are as follows.

1. Horizontal and vertical lines

Horizontal lines are always drawn at a 30 degree angle to the horizontal plane. Vertical lines always stay vertical.

2. Fixed angles

The angle between each of the three faces of an object is always 120 degrees. So, unlike a perspective drawing, where lines converge to a vanishing point, each face of an object will share the same fixed measurements.

3. Parallel lines

Where there are parallel lines, these always remain parallel, across all three faces of a shape.

Isometric drawing tips

Here are some tips that will make it easier to get to grips with isometric drawing.

Base line

Draw a base line on the horizontal plane that cuts through the middle of a line on the grid paper. The dissected equilateral triangles provide the 30 degree angle required for drawing horizontal lines in the isometric projection.

Isometric grid paper

Isometric grid paper can be used as a guide to draw 3D shapes. The grid is made up of equilateral triangles that provide the necessary fixed angles set out in the rules. Equilateral triangles have three 60 degree internal angles. Six triangles pointing inwards create a hexagon, with a pair of triangles together creating a 120 degree inner angle.


Shading each side of a face helps to provide a 3D effect, for example, creating light and dark areas.


This infographic appeared in JONO Design e-news. The e-news is published once every couple of months and each issue contains a specially designed infographic.

Click on the orange button to sign up for JONO Design e-news.

Get in touch to discuss your design requirements

or to request a quote.

> Home | > Document Design | > Templates | > Brand Identity | > Infographics | > Testimonials | > Contact

Copyright © 2015-2024 JONO Design.

Designing solutions with Word