Canvas sizes: What size of canvas should I buy?

You may ask: “Couldn’t I paint on a canvas of any size I choose.”  “Why do I need to know the different sizes of painting surfaces?”

To answer those questions; yes you can paint in a canvas of any size; but there are reasons why you need to be informed about sizes of canvases.  In the old days, artist usually made their own stretcher strips, or order them from their local carpenter, who also provided them with custom frames for their paintings.  All these things are still possible today if you are willing to pay for custom made orders, which can be very expensive.  

The solution: take advantage of the commercially produced stretcher strips and frames, which come in standard,  pre-established sizes.

There are many sizes of canvases and frames, but the most popular are these: (all sizes in inches)

A chart that shows the relationship between sizes, and also group them in proportionate sizes (indicated by color.)  In addition, the diagonal lines (green, purple and red) let you know how short or long a size is in relationship to another.  

Example:  Let us take two sizes: 18 x 24 and 36 x 48. They have the same proportions; but 24 x 36 not only does not share the same proportions with them; but it is proportionally longer. The green diagonal line indicates by how much, where it intersects with the sizes we are trying to relate to.