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What resolution for an A3 (297 × 420 mm) print at 300 DPI?

An A3 (297 × 420 mm) print at 300 DPI needs 3,508 × 4,961 pixels, or 17.4 megapixels. A 12 MP phone photo (4,032 × 3,024) prints at up to 10.08 × 13.44 in at 300 DPI. It needs 2× to cover A3 (297 × 420 mm), which is free.

Last updated 2026-10-05

Pixels you need

Pixels
3,508 × 4,961
Print size
11.69 × 16.54 in (29.7 × 42 cm)
Megapixels
17.4

300 DPI is the photo lab standard for prints you hold in your hand or view at arm's length.

Will your image be big enough?

  • A 12 MP phone photo (4,032 × 3,024) prints at up to 10.08 × 13.44 in at 300 DPI. It needs 2× to cover A3 (297 × 420 mm), which is free.
  • A 1024 × 1024 AI image (1,024 × 1,024) prints at up to 3.41 × 3.41 in at 300 DPI. It needs 4× on Pro, still on your device, then a 1.21× resize to exactly 3,508 × 4,961 for A3 (297 × 420 mm).
  • A 1920 × 1080 screenshot or video frame (1,920 × 1,080) prints at up to 3.6 × 6.4 in at 300 DPI. It needs 4× to cover A3 (297 × 420 mm), on Pro and still on your device.

Calculate for your image

Enter your image size. The upscale button updates to the scale you need.

A3 (297 × 420 mm) at other resolutions

DPIPixelsMegapixelsGood for
300 DPI3,508 × 4,96117.4Photos, close viewing
240 DPI2,806 × 3,96911.1Inkjet, wall prints
200 DPI2,339 × 3,3077.7Large prints
150 DPI1,754 × 2,4804.3Posters
100 DPI1,169 × 1,6541.9Banners

How to prepare the file

  1. Crop your image to the 11.69 × 16.54 shape so the lab does not cut anything off.
  2. Compare your pixels with 3,508 × 4,961. The calculator above does it for you.
  3. Upscale with the smallest scale that reaches the size, then resize to the exact pixels.
  4. Export PNG, or JPG at quality 95, and order the print at this size.

Questions

How many pixels do I need for an A3 (297 × 420 mm) print at 300 DPI?

3,508 × 4,961 pixels: 11.69 × 16.54 inches multiplied by 300 dots per inch, rounded to whole pixels.

Is 300 DPI good enough for A3 (297 × 420 mm)?

300 DPI is the photo lab standard for prints you hold in your hand or view at arm's length.

Can a phone photo be printed at A3 (297 × 420 mm)?

Yes, with 2× upscaling. A 12 MP photo of 4032 × 3024 falls short of 3,508 × 4,961 on its own.

What does DPI mean for a digital file?

Dots per inch is how many image pixels land on each inch of paper. The pixel count is what matters: the DPI field saved in a file does not change the image, the printer scales the pixels to the paper size.

Does upscaling add real detail for printing?

It adds plausible detail: sharper edges and texture instead of the soft blur of ordinary resizing. It cannot recover detail the camera never captured, such as text too small to read.

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