Photo Size Converter
Convert a photo size between millimetres, centimetres, inches and pixels, and see how many fit on a 4×6 print or an A4 sheet. Nothing is uploaded — it all runs on this page.
Common sizes
| Millimetres | 35 × 45 mm |
|---|---|
| Centimetres | 3.5 × 4.5 cm |
| Inches | 1.38 × 1.77 in |
| Pixels at 300 DPI | 413 × 531 px |
| Pixels at 600 DPI | 827 × 1063 px |
| Copies on 4×6 in photo print | 6 |
| Copies on A4 paper | 30 |
Sheet counts leave 4 mm margins and 3 mm gaps for cutting. Print at actual size (100%), not “fit to page”.
Need a photo at this size? We'll add it to your order, along with every common size.
Make this photoHow the conversion works
One inch is exactly 25.4 mm. Pixels depend on resolution: at 300 DPI (dots per inch) — the usual standard for printed photos — a photo has 300 pixels for every inch, so a 2×2 inch photo is 600 × 600 pixels and a 35×45 mm photo is 413 × 531 pixels.
A pixel size on its own doesn't set a printed size: the same 600 × 600 file prints at 2×2 inches at 300 DPI or 1×1 inch at 600 DPI. That's why online forms often give a pixel range, and printed photos a size in millimetres or inches.
Frequently asked questions
How do I convert cm to pixels for a photo?
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Divide by 2.54 to get inches, then multiply by the DPI. At 300 DPI, 1 cm is about 118 pixels — so a 3.5 × 4.5 cm photo is 413 × 531 pixels.
What DPI should a printed ID photo be?
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300 DPI is the usual print standard. Some online forms instead set a pixel size or file-size limit — follow the form's own rule where there is one.
Why does my photo print at the wrong size?
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Most often the printer is set to “fit to page”. Print at actual size (100%) so the photo keeps its millimetre size.
How many photos fit on a 4×6 print?
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It depends on the size: two 2×2 inch photos, six 35×45 mm or 3×4 cm photos, fifteen 1×1 inch photos. The converter works it out for any size, with cutting margins.