Resize image for mini poster

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297 × 420 mm is a portrait 5:7 format (11.69 × 16.54 in). To print it sharply, the image needs about 3508 × 4961 pixels, which is 17.4 megapixels.

This size corresponds to ISO A3.

297 × 420 mm in pixels

Pixels = size in inches × DPI. DPI is a printing instruction, not a quality setting: it says how many pixels are spread over each inch of paper. With the DPI field on Auto, ResizeAny converts at 96 DPI, which suits screens. For print, set 300 DPI. JPG and PNG output stores the DPI value in the file.

Will your photo be sharp enough?

A 12-megapixel phone photo (4000 × 3000) is short of the 3508 × 4961 pixels this size needs at 300 DPI. It would have to be enlarged by about 24%, which looks soft. Use a 150 DPI target (1754 × 2480 px) for a more realistic result, or start with a larger original.

Needed source resolution: 17.4 megapixels or more at 300 DPI.

Matching the 5:7 shape

The output is 5:7. If your photo has another shape, it has to be cropped or it will be stretched. This is how much of each common photo is lost when cropped to fill 5:7:

How to resize an image for mini poster

1. Add your image. Select a photo or drag it onto the box above. JPG, PNG, WebP, AVIF, HEIC and BMP files are accepted, and the file stays on your device.
2. Set the resolution. The preset fills in 297 × 420 mm. Leave DPI on Auto to convert at 96 DPI, or enter 300 DPI for print so the file has enough pixels for a sharp result.
3. Crop if the shape differs. The target shape is 5:7. If your photo is a different shape, crop it first so the print is not stretched.
4. Download and print at 100%. Save as JPG or PNG; the DPI value is stored in the file. Print at 100% scale, not "fit to page", so the physical size stays exact.

Related presets

More in this category: Print, Paper & Photo Sizes. For several photos at once, use the bulk image resizer.