The DPI a photo will print at, for any print size, and whether that is enough
Processed in your browser. Nothing is uploaded. Updated on 25 Oct 2026.The DPI a photo prints at is its pixels divided by the print size in inches, so a 1,200 by 1,800 pixel photo gives 300 DPI on a 4 by 6 inch print and only 150 DPI at 8 by 12 inches. Enter the pixels and the print size and the page shows the DPI across and down, how sharp that should look, and a warning when the photo and the print are different shapes.
DPI at a print size is already chosen, with the print size measured in inches.
Type the Width in pixels and Height in pixels of the photo you plan to print.
Enter the Print width and Print height, or tap a size such as 4×6 in or A4.
Read the DPI, the DPI across and down, and the note on how sharp the print will look.
Pixels, print size and DPI are tied by one rule: pixels = inches × DPI. This page takes any two and gives the third, in centimetres, millimetres and inches, as you type.
Print size from pixels. Enter the width and height in pixels and the DPI. A 4,000 by 3,000 pixel phone photo at 300 DPI prints 33.87 by 25.4 cm, which is 13.33 by 10 inches.
DPI at a print size. Enter the pixels and the size you want to print. The DPI across and down are both shown; when the photo and the print are different shapes, the lower one is what the print gets, and the page says the print will be cropped or bordered.
The rest of the article, and all 6 questions about Photo Size Calculator, are on the Photo Size Calculator page.
At 300 DPI a 35 by 45 mm photo is 413 by 531 pixels: 35 mm is 1.378 inches, and 1.378 times 300 is 413. Tap the passport preset in Pixels for a print to see it, or change the DPI if a form asks for another figure.
A 4 by 6 inch print at 300 DPI needs 1,200 by 1,800 pixels, about 2.2 megapixels. At 200 DPI, 800 by 1,200 pixels is enough for a print that still looks good in the hand. Almost any phone photo has more than either.
No. The DPI number stored in a JPG only suggests a print size; the pixels stay the same. Sharpness in print depends on how many pixels cover each inch, which is why this calculator works from the pixels and the print size alone.
No. The calculator only works out numbers and never opens a picture. Once you know the pixels you need, Resize Image makes the photo that size, with presets for passport, 2 by 2 inch and A4, all inside your browser.
Still stuck? Ask about Photo Size Calculator and anybody who knows can answer. No account needed.
Same job, other tools: Compress Image to 100 KB – Get any photo under 100 KB for forms and portals · Compress Image to 1 MB – Trim a high resolution photo to just under 1 MB · Resize Image for Instagram – Square, portrait and story sizes in one click · Resize Image for LinkedIn – LinkedIn banner at 1584×396 pixels, set and ready to crop · Image Converter – Convert between JPG, PNG, WebP, AVIF, BMP, TIFF and ICO, from ten input formats.
On the related tools: HEIC to PNG – Convert iPhone HEIC photos to lossless PNG.