Standard poster sizes chart
| Size | Inches | Centimetres | Shape | Pixels at 150 DPI | Common for |
|---|---|---|---|---|---|
| 11×17 | Inches: 11 × 17 | Centimetres: 27.9 × 43.2 | Shape: 11:17 | Pixels at 150 DPI: 1,650 × 2,550 | Common for: Flyers, small posters, copy-shop prints |
| A3 | Inches: 11.7 × 16.5 | Centimetres: 29.7 × 42 | Shape: 1:1.41 | Pixels at 150 DPI: 1,754 × 2,480 | Common for: Small posters and art prints outside the US |
| 12×16 | Inches: 12 × 16 | Centimetres: 30.5 × 40.6 | Shape: 3:4 | Pixels at 150 DPI: 1,800 × 2,400 | Common for: Framed prints of phone photos |
| 12×18 | Inches: 12 × 18 | Centimetres: 30.5 × 45.7 | Shape: 2:3 | Pixels at 150 DPI: 1,800 × 2,700 | Common for: Small posters, prints on 13×19 paper |
| 16×20 | Inches: 16 × 20 | Centimetres: 40.6 × 50.8 | Shape: 4:5 | Pixels at 150 DPI: 2,400 × 3,000 | Common for: Framed prints and canvases |
| 16×24 | Inches: 16 × 24 | Centimetres: 40.6 × 61 | Shape: 2:3 | Pixels at 150 DPI: 2,400 × 3,600 | Common for: Mid-size posters and canvases |
| A2 | Inches: 16.5 × 23.4 | Centimetres: 42 × 59.4 | Shape: 1:1.41 | Pixels at 150 DPI: 2,480 × 3,508 | Common for: Wall, classroom and exhibition posters |
| 18×24 | Inches: 18 × 24 | Centimetres: 45.7 × 61 | Shape: 3:4 | Pixels at 150 DPI: 2,700 × 3,600 | Common for: The standard medium poster |
| B2 | Inches: 19.7 × 27.8 | Centimetres: 50 × 70.7 | Shape: 1:1.41 | Pixels at 150 DPI: 2,953 × 4,175 | Common for: Anime, film and gig posters; B sizes in Japan are slightly larger |
| 50×70 cm | Inches: 19.7 × 27.6 | Centimetres: 50 × 70 | Shape: 5:7 | Pixels at 150 DPI: 2,953 × 4,134 | Common for: The standard large poster in European frame ranges |
| 20×30 | Inches: 20 × 30 | Centimetres: 50.8 × 76.2 | Shape: 2:3 | Pixels at 150 DPI: 3,000 × 4,500 | Common for: Large posters and canvas prints |
| 24×30 | Inches: 24 × 30 | Centimetres: 61 × 76.2 | Shape: 4:5 | Pixels at 150 DPI: 3,600 × 4,500 | Common for: Large canvases and wall portraits |
| A1 | Inches: 23.4 × 33.1 | Centimetres: 59.4 × 84.1 | Shape: 1:1.41 | Pixels at 150 DPI: 3,508 × 4,967 | Common for: Large posters and event signage |
| 24×36 | Inches: 24 × 36 | Centimetres: 61 × 91.4 | Shape: 2:3 | Pixels at 150 DPI: 3,600 × 5,400 | Common for: The standard large poster; movie reprints |
| 27×40 | Inches: 27 × 40 | Centimetres: 68.6 × 101.6 | Shape: 27:40 | Pixels at 150 DPI: 4,050 × 6,000 | Common for: Theatrical movie one-sheets |
| A0 | Inches: 33.1 × 46.8 | Centimetres: 84.1 × 118.9 | Shape: 1:1.41 | Pixels at 150 DPI: 4,967 × 7,022 | Common for: Conference and display posters |
| 36×48 | Inches: 36 × 48 | Centimetres: 91.4 × 121.9 | Shape: 3:4 | Pixels at 150 DPI: 5,400 × 7,200 | Common for: Trade-show boards, engineering prints |
150 DPI is sharp from a step or two away, which is how posters are seen. A sizes are exact in millimetres; their inches are rounded.
Small, medium and large are not official names, but print shops and frame makers use them consistently: 11×17 is the small poster, 18×24 the medium, 24×36 the large. 12×18 and 20×30 are their 2:3 cousins, and A sizes are the standard almost everywhere outside North America.
Pick the size by your photo’s shape
Most people pick the poster size the frame shop had, and that is how photos get cropped. Every size has a shape, and a photo only fills it without losing anything when the shapes match. Check yours first:
| Your photo | Its shape | Poster sizes with the same shape |
|---|---|---|
| Phone camera (most iPhones and Androids) | Its shape: 3:4 | Poster sizes with the same shape: 12×16, 18×24, 36×48 |
| DSLR or mirrorless camera, 35mm film | Its shape: 2:3 | Poster sizes with the same shape: 12×18, 16×24, 20×30, 24×36 |
| A file made for A4 | Its shape: 1:1.41 | Poster sizes with the same shape: A3, A2, A1, A0 |
| A photo prepared for 8×10 | Its shape: 4:5 | Poster sizes with the same shape: 16×20, 24×30 |
Shapes are short side to long side. Landscape works the same way, turned on its side.
When the shapes differ, the print shop crops to fill the poster. A phone photo printed at 24×36 loses about a ninth of its width; a camera photo at 18×24 loses about a ninth of its height. On a poster that is often the sky, the floor, or whoever was standing at the edge. You can extend the photo to the poster’s shape instead, so the whole picture stays in.
How many pixels a poster needs
Fewer than most people think. The 300 DPI rule is for prints held in the hand; a poster is looked at from a few feet away, where the eye resolves only about 96 pixels per inch. That is why 150 DPI is the usual poster target, and why the chart above uses it. The large-format printing guide has the viewing-distance rule in full.
- A 12-megapixel phone photo (3,024 × 4,032) is about 168 DPI at 18×24: enough as it is.
- The same photo at 24×36 is about 126 DPI: fine from across a room, soft up close.
- A photo saved from Facebook or Instagram is much smaller, often around 2,000 pixels on the long side or less, and looks soft at any poster size.
- Typing a new DPI into the file doesn't add pixels. See how to convert an image to 300 DPI for what does.
If your photo is short of pixels, an upscale rebuilds detail at poster size. Resly delivers up to 16 megapixels, which is 3,265 × 4,898 pixels at 24×36, about 136 DPI.