🖨️ Print Size & DPI Calculator

Enter your image's pixel dimensions and desired print size to calculate the print resolution in DPI (dots per inch).

Pixels spread over inches

DPI is not stored in the file - it only exists once you decide how big the print is. The tool divides one by the other, and does it separately for each edge:

DPI across = pixel width  / print width in inches
DPI down   = pixel height / print height in inches
pixels needed = target DPI × inches

The defaults are a 3000 × 2000 file at 10 × 6.67 inches: 3000 / 10 = 300 DPI across, and 2000 / 6.67 = 300 down. The quality label is graded off the width figure alone - 300 and over reads Excellent, 150 to 299 Good, and anything lower is flagged for large-format work seen from a distance.

How big that file goes

Print sizeDPI from 3000 x 2000Verdict
6 × 4 in500beyond what the eye resolves
10 × 6.67 in300photo quality
12 × 8 in250fine in a frame
20 × 13.3 in150good at arm's length
30 × 20 in100a wall piece, viewed back

The boxes take inches only, so divide centimetres by 2.54. A4 is 11.7 × 8.3 in.

If the two DPI numbers come back different, your print shape does not match your image shape and the lab will crop or stretch it. A 3:2 file asked for 10 × 8 in gives 300 across but 250 down - crop it to 4:5 first.

Frequently asked questions

How big can I print a 24 megapixel photo?

A 6000 × 4000 file gives 20 × 13.3 inches at 300 DPI, or 40 × 26.7 inches at 150 DPI. Big prints are seen from further back, so the second figure is the honest one.

Is 150 DPI good enough to print?

For anything bigger than about A3, yes. 300 DPI matters at reading distance, where the eye resolves roughly 300 dots per inch at 12 inches. Posters run at 150, billboards at 20, and both look sharp from where you stand.

How many pixels do I need for an 8 x 10 print?

2400 × 3000 at 300 DPI, or 1200 × 1500 if 150 will do. Multiply the inches by the DPI you want - and note 8 × 10 is 4:5, not the 3:2 your camera shoots.