Poster pixel requirements scale directly with print size and DPI. A 24×36in poster needs 7,200 × 10,800 pixels at 300 DPI, but only 3,600 × 5,400 pixels at the more typical poster target of 150 DPI. The full table below covers every standard size at both.
Check standard poster dimensions and required resolution.
Open Poster Size Calculator| Poster size | 150 DPI (px) | 300 DPI (px) |
|---|---|---|
| 8 × 10 in | 1,200 × 1,500 | 2,400 × 3,000 |
| 11 × 17 in | 1,650 × 2,550 | 3,300 × 5,100 |
| 12 × 18 in | 1,800 × 2,700 | 3,600 × 5,400 |
| 16 × 20 in | 2,400 × 3,000 | 4,800 × 6,000 |
| 18 × 24 in | 2,700 × 3,600 | 5,400 × 7,200 |
| 20 × 30 in | 3,000 × 4,500 | 6,000 × 9,000 |
| 24 × 36 in | 3,600 × 5,400 | 7,200 × 10,800 |
| A4 (210 × 297 mm) | 1,240 × 1,754 | 2,480 × 3,508 |
| A3 (297 × 420 mm) | 1,754 × 2,480 | 3,508 × 4,961 |
| A2 (420 × 594 mm) | 2,480 × 3,508 | 4,961 × 7,016 |
| A1 (594 × 841 mm) | 3,508 × 4,967 | 7,016 × 9,933 |
DPI requirements exist to match print density to how closely a viewer will look. A photo held 12 inches away benefits from 300 DPI; a poster mounted on a wall is typically viewed from several feet back, where the eye simply can't resolve that same density. Printing at 300 DPI for a large poster mostly just demands more source resolution without a visible sharpness benefit — 150 DPI (or less, for very large or distant pieces like banners) is the standard practical target.
Pixel dimensions follow directly from the same formula at every size: pixels = inches × DPI. A 12×18in print at 300 DPI needs 3,600×5,400px; a 24×36in poster — exactly double the width and height — needs exactly double the pixels on each axis, or 7,200×10,800px, and four times the total pixel count. That's the practical reason large-format prints usually drop to a lower DPI target instead of scaling resolution requirements linearly with size.
A 24×36in poster is 7,200 × 10,800 pixels at 300 DPI, or 3,600 × 5,400 pixels at 150 DPI.
Usually not. Posters are typically viewed from several feet away, where the eye can't resolve 300 DPI detail — 150 DPI, or sometimes less, is standard for large-format prints. See Best DPI for Common Print Formats for viewing-distance guidance.
Pixel count scales directly with physical size at a fixed DPI — doubling the print dimensions doubles the pixels needed on each axis, and quadruples the total pixel count. That's why a 24×36in poster at 300 DPI needs far more source resolution than an 8×10in print at the same DPI.
Print at 150 DPI instead, since posters are viewed from a distance and rarely need 300 DPI; print smaller; or start from a higher-resolution source if one exists. Upscaling can fill the pixel count but doesn't recover missing detail.
A-series sizes are the ISO 216 standard used across most of the world for posters and prints. US-centric sizes like 11×17in and 24×36in are more common in North America; check what your print shop or framer stocks before choosing.
