THE TOOLKIT
Pixels to print size.
Work out how large an image can print at a chosen pixel density. Enter the original pixel dimensions, before any resizing.
The formula
Print size (inches) = image size (pixels) ÷ PPI
Multiply inches by 2.54 for centimetres, or by 25.4 for millimetres. Width and height are calculated separately, preserving the image’s aspect ratio.
Worked example: a 3000 × 2400 pixel image
At 300 PPI, 3000 ÷ 300 = 10 inches wide, and 2400 ÷ 300 = 8 inches high. The result is 25.4 × 20.32 cm. At 150 PPI, the same pixels cover 50.8 × 40.64 cm, with less detail per unit of printed area.
Will changing PPI improve a blurry photo?
No. Changing the PPI value alone does not recover missing detail. Resampling can add pixels, but those new pixels are calculated from existing information. Check a print at the intended viewing distance before committing to a larger run.
Why does my image not fit A4?
The image and the sheet can have different aspect ratios. Fit preserves the whole image and can leave blank space; fill covers the sheet and can crop the image. Compare the A4 pixel dimensions with your file.
Sources & method
- Adobe printed image resolution · Pixel dimensions, resolution and physical print size
- Adobe printer resolution · Printer DPI and image PPI
Dimensions use the published nominal sizes. Conversions and calculator examples are derived from those values. Calculated results are estimates for planning, not printer calibration.
Keep things in proportion.
All print toolsCheck the image itself
Have an image file? Check its pixel dimensions, cropping and borders at a chosen physical print size. Compare the controlled resolution samples and actual-size print proofs to see how the same detail is sampled at different pixel densities.