Print projects demand precise image specifications — the wrong resolution results in blurry, pixelated output that wastes ink and paper. This guide covers the exact specifications for A1 Poster Size and shows you how to resize your images to the correct dimensions using the free tools at imgresizr.com.
Image Specifications for A1 Poster Size
| Specification | Value |
|---|---|
| Resolution (print quality) | 300 DPI |
| Standard A4 at 300 DPI | 2480 × 3508 px |
| Standard A3 at 300 DPI | 3508 × 4961 px |
| Colour mode | CMYK for commercial, RGB for home print |
| Bleed area | 3 mm on each edge |
| File format | PNG or TIFF |
How to Resize Images for A1 Poster Size at imgresizr.com
Upload your image to imgresizr.com. Select the Resize tab. Enter the correct dimensions for A1 Poster Size as shown in the table above. Use the lock icon to maintain the aspect ratio if you only know one dimension. Click Resize to process your image. Download the result — your image is now correctly sized for A1 Poster Size. All processing happens in your browser; your image is never uploaded to any server.
Tips for A1 Poster Size
- Always work at 300 DPI or higher for any image that will be printed — screen-resolution images look blurry in print
- Add 3 mm bleed on all edges if the design extends to the paper edge
- Convert to CMYK colour mode if your printer uses CMYK — RGB colours can shift significantly in print
- Save a lossless PNG or TIFF master file before compressing for web or email use
- Proof your print on a home printer before sending to a commercial printer to catch dimension errors early
Resize images for A1 Poster Size instantly, free at imgresizr.com.