12 × 18 inch poster size in pixels
12 × 18 inch poster is 12 × 18 in. In pixels that is 3600 × 5400 at 300 DPI for print and 864 × 1296 at 72 DPI.
12 × 18 inches is a small poster with the 2:3 shape of a camera frame, so a photo fills it without cropping. It measures 12 × 18 in, or 304.8 × 457.2 mm.
| Resolution | Pixels (portrait) | With 0.125 in bleed | Megapixels | Uncompressed |
|---|---|---|---|---|
| 72 DPI | 864 × 1296 | 882 × 1314 | 1.1 | 3.2 MB |
| 96 DPI | 1152 × 1728 | 1176 × 1752 | 2 | 5.7 MB |
| 100 DPI | 1200 × 1800 | 1225 × 1825 | 2.2 | 6.2 MB |
| 150 DPI | 1800 × 2700 | 1838 × 2738 | 4.9 | 14 MB |
| 200 DPI | 2400 × 3600 | 2450 × 3650 | 8.6 | 25 MB |
| 240 DPI | 2880 × 4320 | 2940 × 4380 | 12 | 36 MB |
| 300 DPI | 3600 × 5400 | 3675 × 5475 | 19 | 56 MB |
| 400 DPI | 4800 × 7200 | 4900 × 7300 | 35 | 99 MB |
| 600 DPI | 7200 × 10800 | 7350 × 10950 | 78 | 222 MB |
| 1200 DPI | 14400 × 21600 | 14700 × 21900 | 311 | 890 MB |
Landscape is the same numbers the other way round. Pixels are rounded to the nearest whole pixel. The last column is 8-bit RGB before compression.
Which resolution to use for 12 × 18 inch poster
For print that will be held and read, use 300 DPI: 3600 × 5400 pixels, 19 megapixels. A sheet this large is usually seen from further back, so 150 DPI (1800 × 2700 pixels) is often enough and a quarter of the file. For a screen, the DPI number does nothing; only the pixel size matters.
Will a photo fill it?
- A 12 megapixel phone photo (4000 × 3000 pixels), cropped to fill 12 × 18 inch poster, prints at 222 DPI: fine from a step back, a little soft up close.
- A 24 megapixel camera photo (6000 × 4000 pixels), cropped to fill 12 × 18 inch poster, prints at 333 DPI: sharp at any distance.
- A 48 megapixel photo (8000 × 6000 pixels), cropped to fill 12 × 18 inch poster, prints at 444 DPI: sharp at any distance.