Print Design
Poster Sizes UK: A4 to A0 and Inch Sizes, in mm and Pixels
Poster sizes from A4 to A0 and the common inch sizes, with pixel sizes at 150dpi and which size to choose.
Published 22 October 20264 min read
A sizes and inch sizes
Most UK posters use A sizes. Each size is double the area of the one below it, so an A2 poster is two A3s side by side. Imperial sizes such as 30 × 20in and 40 × 30in are common for frames and display boards. The pixel sizes are at 150dpi at the finished size, which is plenty for a poster seen from a step or two away.
| Size | Millimetres | Inches | Pixels at 150dpi |
|---|---|---|---|
| A4 | 210 × 297mm | 8.3 × 11.7in | 1240 × 1754px |
| A3 | 297 × 420mm | 11.7 × 16.5in | 1754 × 2480px |
| A2 | 420 × 594mm | 16.5 × 23.4in | 2480 × 3508px |
| A1 | 594 × 841mm | 23.4 × 33.1in | 3508 × 4967px |
| A0 | 841 × 1189mm | 33.1 × 46.8in | 4967 × 7022px |
| 30 × 20in | 762 × 508mm | 30 × 20in | 4500 × 3000px |
| 40 × 30in | 1016 × 762mm | 40 × 30in | 6000 × 4500px |
| 60 × 40in | 1524 × 1016mm | 60 × 40in | 9000 × 6000px |
Which size to choose
A4 and A3 suit noticeboards, windows and small frames. A2 and A1 are the usual sizes for shop windows, events and walls, where people see them from across the street or the room. A0 and the large inch sizes are for exhibitions, receptions and big walls, when you need to be seen from further away.
Bleed, safe area and resolution
Add 3mm of bleed on every edge and keep text and logos at least 10mm inside the trim. Images need to be 150dpi at the full poster size: a photo that looks sharp on screen can look soft at A1, so check its pixel size against the table. I check every file before it’s printed and tell you if anything will look soft.
Paper and PVC
Posters up to A1 come on 150gsm to 350gsm silk or 170gsm uncoated paper, with optional matt or gloss lamination. Large format posters up to 60 × 40in come on 170gsm or 250gsm silk, or on 220 or 400 micron matt white PVC. For lightboxes and illuminated frames, backlit posters are printed on backlit film.
Frequently asked questions
- What size is A1 in cm?
- A1 is 59.4 × 84.1cm (594 × 841mm), about 23.4 × 33.1 inches.
- What size is A0?
- A0 is 841 × 1189mm, about 33.1 × 46.8 inches. It’s the largest A size, with an area of one square metre.
- What resolution does a poster need?
- 150dpi at the full printed size. For an A1 poster that’s about 3508 × 4967 pixels.
- What’s the biggest poster you print?
- A0 and 60 × 40in (1524 × 1016mm), printed on one side on silk paper or matt white PVC.
Written by Ross Boag
Need help with design, websites or branding?
Ross Boag is a senior freelance graphic designer in Glasgow with 12+ years of agency and in-house experience, for brands including Hilton, Volvo and Jim Beam. He also designs logos and brand identities and websites, and prints the work through his online print shop, for businesses across Glasgow, Scotland and the UK.