Poster Size: 11x17, 18x24 and 24x36 (2026)
The standard poster sizes in the US are 11 x 17 inches (small), 18 x 24 inches (medium) and 24 x 36 inches (large). Outside the US, posters follow the A sizes: A3, A2, A1 and A0. At 300 dpi, a 24 x 36 inch poster is 7200 x 10800 pixels.
Large, 610 x 914 mm. The standard big poster in the US.
Standard poster sizes in inches, cm, mm and pixels
Here's every common poster size in portrait, with its dimensions as width x height. Pixels are at 300 dpi, the standard for print you look at up close.
| Size | Inches | Centimeters | Millimeters | Pixels at 300 dpi |
|---|---|---|---|---|
| 11 x 17 (small) | 11 x 17 | 27.9 x 43.2 | 279 x 432 | 3300 x 5100 |
| 12 x 18 | 12 x 18 | 30.5 x 45.7 | 305 x 457 | 3600 x 5400 |
| 16 x 20 | 16 x 20 | 40.6 x 50.8 | 406 x 508 | 4800 x 6000 |
| 18 x 24 (medium) | 18 x 24 | 45.7 x 61 | 457 x 610 | 5400 x 7200 |
| 20 x 30 | 20 x 30 | 50.8 x 76.2 | 508 x 762 | 6000 x 9000 |
| 24 x 36 (large) | 24 x 36 | 61 x 91.4 | 610 x 914 | 7200 x 10800 |
| 27 x 40 (movie poster) | 27 x 40 | 68.6 x 101.6 | 686 x 1016 | 8100 x 12000 |
| 36 x 48 | 36 x 48 | 91.4 x 121.9 | 914 x 1219 | 10800 x 14400 |
| A3 | 11.69 x 16.54 | 29.7 x 42 | 297 x 420 | 3508 x 4961 |
| A2 | 16.54 x 23.39 | 42 x 59.4 | 420 x 594 | 4961 x 7016 |
| A1 | 23.39 x 33.11 | 59.4 x 84.1 | 594 x 841 | 7016 x 9933 |
| A0 | 33.11 x 46.81 | 84.1 x 118.9 | 841 x 1189 | 9933 x 14043 |
In feet, 24 x 36 inches is 2 x 3 feet, 18 x 24 is 1.5 x 2 feet and 36 x 48 is 3 x 4 feet.
Or describe your event and the AI poster maker designs a 2:3 poster from scratch, the shape of 24 x 36.
Which poster size should you use?
Pick the size by where the poster hangs and how far away people read it.
Small: 11 x 17, 12 x 18 or A3
For notice boards, shop windows and doors. 11 x 17 is two US Letter sheets side by side.
Medium: 16 x 20, 18 x 24 or A2
For rooms, hallways, events and frames. 18 x 24 is the common medium poster in the US, and 16 x 20 is a common frame size.
Large: 24 x 36 or A1
For walls, lobbies and anything read from across a room. 24 x 36 is the standard large poster in the US.
Extra large: 27 x 40, 36 x 48 or A0
27 x 40 is the movie poster size, called a one-sheet. 36 x 48 and A0 are common for conference posters and big halls.
School projects
Poster board is 22 x 28 inches, and a tri-fold display board is 36 x 48 inches.
Poster aspect ratios: why 18 x 24 and 24 x 36 don't swap
Poster sizes come in a few shapes, called aspect ratios. A design scales without cropping only between sizes with the same ratio.
| Aspect ratio | Poster sizes |
|---|---|
| 2:3 | 12 x 18, 16 x 24, 20 x 30, 24 x 36 |
| 3:4 | 18 x 24, 36 x 48 |
| 4:5 | 16 x 20 |
| 1:1.414 | A3, A2, A1, A0 |
| Close to 2:3 | 11 x 17, 27 x 40 |
24 x 36 has exactly twice the area of 18 x 24 (864 against 432 square inches), but it's a different shape: 2:3 against 3:4. A design made for one doesn't scale to the other without cropping.
Krumzi's posters are 2:3, so they print at 12 x 18, 16 x 24, 20 x 30 or 24 x 36 inches with nothing cropped.
Check any size with the 2:3 aspect ratio calculator.
Poster size in pixels and resolution
The standard resolution for a poster you look at up close is 300 dpi: multiply the inches by 300. Large posters are seen from farther away, and many print shops accept 150 dpi for them.
| Size | Pixels at 300 dpi | Pixels at 150 dpi |
|---|---|---|
| 18 x 24 | 5400 x 7200 | 2700 x 3600 |
| 24 x 36 | 7200 x 10800 | 3600 x 5400 |
Ask your print shop which resolution it wants before you export.
For a landscape (horizontal) poster, swap the numbers. 24 x 36 in landscape is 36 x 24 inches, or 10800 x 7200 pixels at 300 dpi.
In Photoshop, type the size in inches and set the resolution to 300 pixels per inch. In Canva, pick a custom size and switch the unit to inches. In Figma, which works in pixels, type the pixel size from the table.
Krumzi's free poster is 1200 x 1800 px, sharp on screens and in small prints. For a big print, the 4x export (once your plan starts) is 4800 x 7200 px: 300 dpi at 16 x 24 and 200 dpi at 24 x 36.
Poster bleed and safe margin
Bleed is extra background past the edge. The print shop prints a little bigger and trims it off, so color runs right to the edge. The common bleed is 0.125 inch (3 mm) on every side.
A 24 x 36 poster with bleed is 24.25 x 36.25 inches, or 7275 x 10875 pixels at 300 dpi.
The safe margin is the strip just inside the trim line. Keep words and logos inside it, because trimming can shift slightly. Your print shop's template shows how wide it is.
Krumzi's print PDFs come at their physical size with an optional 0.125 inch bleed, and Krumzi keeps words away from the edges so nothing important gets trimmed.
US poster sizes vs A sizes
The US uses inch sizes. Most other countries use the A sizes, which all share one shape (1:1.414), so a design scales from A3 to A0 without cropping.
| US size | Closest A size | A size in inches | A size in mm |
|---|---|---|---|
| 11 x 17 in | A3 | 11.69 x 16.54 | 297 x 420 |
| 18 x 24 in | A2 | 16.54 x 23.39 | 420 x 594 |
| 24 x 36 in | A1 | 23.39 x 33.11 | 594 x 841 |
| 36 x 48 in | A0 | 33.11 x 46.81 | 841 x 1189 |
None of the pairs match exactly, so a design made for a US size needs adjusting for an A size, and the other way round.
Each A size is half the one before it: A1 is half of A0, A2 is half of A1 and A3 is half of A2.
Making something smaller? The flyer size guide covers US Letter, A4, A5 and the handout sizes.
Every poster size in pixels
Portrait sizes at 300 dpi, ready to copy into your design app. For landscape, swap the width and height.
Or let Krumzi design the poster for you.
Tell it what's happening, when and where. The AI poster maker designs a 2:3 poster from scratch in 1 to 3 minutes, every word real text. One poster a week is free, no signup, downloaded with a small watermark.
Make a poster with AIPrint design tips that matter
Getting the size right is the start. These keep a printed poster sharp and readable, with nothing important trimmed off.
Pick the shape before the size
2:3 prints at 12 x 18, 20 x 30 and 24 x 36. 18 x 24 is 3:4 and 16 x 20 is 4:5. Design for the shape you'll print, or plan to crop.
Ask your print shop about resolution
300 dpi is safe for anything seen up close. Many print shops accept 150 dpi for large posters, which halves the pixels on each side.
Write for reading at a distance
Use a headline you can read from 10 feet away, and keep the whole poster to about 20 words.
Add bleed for edge-to-edge color
Extend the background 0.125 inch (3 mm) past every edge. A 24 x 36 poster with bleed is 24.25 x 36.25 inches.
Frequently asked questions
In the US, the standard poster sizes are 11 x 17 inches (small), 18 x 24 inches (medium) and 24 x 36 inches (large). Movie posters are 27 x 40 inches. Outside the US, posters use the A sizes: A3, A2, A1 and A0.
Yes. 24 x 36 inches (2 x 3 feet, or 610 x 914 mm) is the standard large poster size in the US. It's a 2:3 shape, and at 300 dpi it's 7200 x 10800 pixels.
Yes. 18 x 24 inches (457 x 610 mm) is the standard medium poster size in the US. It's a 3:4 shape, and at 300 dpi it's 5400 x 7200 pixels.
18 x 24 inches is 1.5 x 2 feet, or 45.7 x 61 cm. It's the standard medium poster in the US, with half the area of a 24 x 36.
No. 24 x 36 has exactly twice the area of 18 x 24 (864 against 432 square inches), and it's a different shape: 2:3 against 3:4. A design made for one won't scale to the other without cropping.
Yes. 11 x 17 inches, also called tabloid, is the standard small poster size. It's two US Letter sheets side by side, and at 300 dpi it's 3300 x 5100 pixels.
No. 11 x 17 is twice the size of 8.5 x 11: two US Letter sheets side by side. 8.5 x 11 is the standard flyer size, covered in our flyer size guide, and 11 x 17 is a small poster.
12 x 16 inches (305 x 406 mm) is a common frame and art print size, but a less common poster size than 11 x 17 or 12 x 18. It's a 3:4 shape, the same as 18 x 24, and at 300 dpi it's 3600 x 4800 pixels.
Both are poster sizes. A3 (297 x 420 mm) is a small poster, close to 11 x 17. A2 (420 x 594 mm) is a medium poster, a little smaller than 18 x 24. A1 and A0 are the large sizes.
It's a medium poster. 16 x 20 inches (406 x 508 mm) is bigger than 11 x 17 and smaller than 18 x 24. It's a 4:5 shape, and a common frame size.
Yes, with a mat. The mat leaves 1 inch at each side and 2 inches at the top and bottom.
A poster fits a frame of its own size. Common poster frames in the US are 11 x 17, 16 x 20, 18 x 24, 24 x 36 and 27 x 40 inches. With a mat, pick a frame one size up: a 16 x 20 poster fits an 18 x 24 frame.
Only by tiling it. Open the poster as a PDF and choose the poster or tile option in your PDF reader's print dialog. It prints across many letter sheets that you trim and tape together. For a clean result, a print shop is the usual route.
At 300 dpi, an 11 x 17 poster is 3300 x 5100 pixels, an 18 x 24 is 5400 x 7200 and a 24 x 36 is 7200 x 10800. Many print shops accept 150 dpi for large posters, which makes a 24 x 36 poster 3600 x 5400 pixels. Ask your print shop which it wants.
A movie poster, called a one-sheet, is 27 x 40 inches (686 x 1016 mm). At 300 dpi that's 8100 x 12000 pixels. Its shape is close to 2:3.
Social media uses its own sizes. An Instagram post is 1080 x 1350 pixels (4:5) and a story is 1080 x 1920 pixels (9:16). A print poster is a different shape, so make a version laid out for each size instead of posting the print file. See the Instagram post size guide and the Instagram story size guide.
Related size guides
Designing for one platform usually means designing for several. Here's what people look up next.
Flyer
US Letter, A4, A5, half page and DL.
Instagram Post
Portrait. Takes up the most feed real estate.
Instagram Story
Vertical, disappears in 24 hours.
Related reading
Still picking a design tool? These two settle the Canva question.
- Canva alternatives15 tools tested, free and paid, ranked by what they are actually good at.
- Krumzi vs CanvaSide by side on process, editing, brand and price.