Print size depends on the pixels remaining after your chosen crop, plus the quality of the source. Calculate a starting size, inspect the actual print preview and use a proof when the result matters.
Megabytes alone do not answer the question. A large file can still contain a blurred face, and a small message copy may not be the best version available.
Begin with the best source
Use the original camera file or best scan where available. Ask the photographer for a larger original if you only have a reduced message or social-media copy.
Keep the source unchanged and prepare a separate print copy. Inspect focus, motion blur and meaningful detail before calculating. An imperfect but treasured photo may still make a worthwhile modest print.
Read the image’s width and height in pixels in your viewer’s information panel. Check the dimensions again after cropping; a tight face crop can remove much of the original image.
Use a simple calculation
Print length in centimetres equals pixels ÷ chosen ppi × 2.54. Calculate width and height separately. Ppi means pixels per inch; 2.54 converts inches to centimetres.
At 300 ppi, a 3000 × 2400 pixel image gives approximately 25.4 × 20.3 cm. If a crop leaves 1500 × 1200 pixels, that falls to about 12.7 × 10.2 cm at the same density.
Three hundred ppi is a common close-viewing planning reference, not a universal pass mark. The printer’s requirements, viewing distance, paper and source quality still matter.
At 200 ppi the original 3000 × 2400 file would spread across about 38.1 × 30.5 cm. That is more paper, not newly captured information. Judge whether the result suits its intended use.
Match the picture’s shape to the paper
A 3000 × 2400 image is 5:4. A nominal 15 × 10 cm print is 3:2. Filling one rectangle with the other usually needs cropping; keeping the whole image can leave borders.
For a family group, preserving everyone’s face and feet may matter more than edge-to-edge coverage. Move a crop deliberately instead of accepting the first centred suggestion.
Check the provider’s actual size. Some centimetre labels are rounded from inch-based products. Keep borders, inscriptions and historical context in the source even if your decorative print uses a different crop.
A resolution label cannot create detail
Changing a ppi label without resampling does not add pixels. Resampling changes pixel count, and enlargement tools may estimate or generate new detail.
An AI enlargement may look more convincing without proving those facial features or letters existed in the source. Inspect it carefully and keep the unaltered version.
Try a smaller print, less aggressive crop or better source before buying an enlargement tool. The emotional value of a photograph does not depend on making it fill a wall.
Check the outgoing file and order preview
Export the print copy, reopen it and confirm dimensions and framing. The editor’s current view is not necessarily the file the service receives.
In the order preview, check filename, quantity, product size, borders and crop. Investigate low-resolution warnings: you may have chosen the wrong export or a much tighter crop than intended.
Review automatic enhancement choices too. An extra adjustment may change the edit you already approved. Keep the setting with the proof record so you can repeat the result.
Let a modest proof settle the uncertain parts
For a significant enlargement or several gifts, consider one proof on the intended paper and finish. Inspect faces, shadows, bright areas and framing in ordinary viewing light.
If it is too dark or the crop is uncomfortable, identify that specific problem before making a new version. A bright screen is not a reliable promise of printed appearance.
Keep the approved file and a brief record of dimensions, paper, enhancement setting and date. Repeat the shape check for a different product rather than assuming one export fits every size.
Next step
Check a photo book layout before ordering if the picture will sit on a book page.
Sources and scope
Researched 9 September 2026: Adobe’s printed-resolution explanation. Examples are mathematical calculations, not tested prints or enlargement results.