Print size · ISO

A3 (297×420 mm) print size

Exactly how many pixels a A3 (297×420 mm) print needs — and how much your camera's frame gets cropped.

17.4 MP
Needed at 300 DPI
7.7 MP
Needed at 200 DPI
42.0×29.7 cm
Size in cm
1.41:1
Aspect ratio
30 in
Typical viewing distance

Pixels needed for a A3 (297×420 mm) print#

At normal viewing distance (≈1.5× the diagonal, 0.8 m) about 200 DPI is indistinguishable from 300 DPI for most viewers.

ResolutionQualityPixel dimensionsMegapixels
360 DPIExceptional (close inspection)5,954 × 4,208 px25.1 MP
300 DPIPhoto-lab standard4,962 × 3,507 px17.4 MP
240 DPIFine-art inkjet3,970 × 2,806 px11.1 MP
200 DPILarge wall print3,308 × 2,338 px7.7 MP
150 DPIPoster, viewed from 1 m+2,481 × 1,754 px4.4 MP
100 DPIBillboard / banner1,654 × 1,169 px1.9 MP

Cropping from your camera#

Camera aspect ratioWhat happensImage kept
3:2 (full frame, APS-C)Crop the long side94%
4:3 (MFT, phones)Crop the short side94%
16:9Crop the long side80%
1:1Crop the short side71%
Maximum print size—
In centimetres—
Megapixels · aspect ratio—

Will my camera be enough?#

A 24 MP camera (6000 × 4000 px) prints 363 DPI on the long side at A3 (297×420 mm) — more than enough. A 12 MP phone (4032 × 3024) gives 244 DPI. See the 18 megapixel guide.

Popular fine-art print size.

Other print sizes#

Wallet (2.5×3.5 in)3.5×5 in4×6 in5×5 in5×7 in6×8 in8×8 in8×10 in8.5×11 in (US Letter)8×12 in10×10 in11×14 in12×12 in11×17 in (Tabloid)12×16 in12×18 in13×19 in (Super B / A3+)16×20 in16×24 in18×24 in20×24 in20×30 in24×30 in24×36 in30×40 in40×60 inA6 (105×148 mm)A5 (148×210 mm)A4 (210×297 mm)A3+ (329×483 mm)A2 (420×594 mm)A1 (594×841 mm)A0 (841×1189 mm)10×15 cm13×18 cm20×30 cm30×40 cm30×45 cm40×60 cm50×70 cm60×90 cm

Frequently asked questions#

How many megapixels do I need for a A3 (297×420 mm) print?

17.4 MP for 300 DPI photo-lab quality, 7.7 MP at 200 DPI, and 4.4 MP at 150 DPI.

What resolution is A3 (297×420 mm) at 300 DPI?

4,962 × 3,507 pixels.

Last updated October 03, 2026 · How we calculate · Sources