Pixels ÷ PPI = print size
Divide the pixel width and height by the print resolution in pixels per inch. A 3840 × 2160 image at 300 PPI prints at 12.8 × 7.2 inches, or about 32.5 × 18.3 cm. At 150 PPI, the dimensions double.
PPI describes image pixels per printed inch. Printer DPI describes ink dots and is not the same setting. Changing a resolution label alone does not add pixels or recover detail.
Match the shape as well as the resolution
A 4:3 photo and an 8 × 10 inch print have different aspect ratios. Filling the paper crops part of the image; fitting the whole image leaves borders. The calculator compares the pixel dimensions needed to fill a selected print size, allowing rotation.
When upscaling helps
Upscaling can provide more pixels for a larger print, but fine detail is estimated. Start from the largest available original, inspect the result and use a small test print before ordering a large batch. The right PPI depends on viewing distance, print process and the printer’s requirements.
Frequently asked questions
Does this upload my photo?
Reading dimensions stays in your browser and uses no credits. Phone transfers use temporary encrypted storage. AI processing uploads the image when you submit that task.
Does the calculator change my image?
The calculation keeps your original unchanged. Continue with the chosen print size to export locally when you have enough pixels, or send the same image for AI upscaling before export.
Is 300 PPI always required?
No. It is a common target for close viewing, but larger prints viewed from farther away may use less. Follow your print provider’s requirements.