How to Use the Canvas Size Ratio Calculator
Choosing the right canvas proportions before you start painting prevents frustrating restretches and wasted materials. Pick a preset ratio — square, photo, golden ratio, widescreen — or enter a custom W:H ratio, then type your desired width to instantly see the height and area. The calculator also suggests the closest standard US canvas size so you can buy off-the-shelf frames.
Common Standard US Canvas Sizes
| Size | Approx. Ratio | Common Use |
|---|---|---|
| 8 × 10" | 4:5 | Small studies, portraits |
| 16 × 20" | 4:5 | Medium paintings |
| 18 × 24" | 3:4 | Standard landscape/portrait |
| 24 × 36" | 2:3 | Large works |
Frequently Asked Questions
Classic portrait ratios are 3:4 or 2:3 (taller than wide). The golden ratio (1:1.618) also works beautifully for both portraits and landscapes. Try a few ratios in the calculator to compare before cutting or buying canvas.
Yes — just enter your width in cm. The result will be in cm and cm². The standard size suggestion uses US inch-based sizes, so ignore that column if you're working in metric.