How to Resize an Image in CM vs Pixels

European and Asian application forms often specify 3.5×4.5 cm or similar. Enter those values directly in ExactPic's resize tool.

A digital image is measured in pixels, so a centimeter size only becomes exact once you fix the DPI (dots per inch, sometimes written PPI). The formula is: pixels = cm ÷ 2.54 × DPI.

For example, 3.5 × 4.5 cm is about 413 × 531 px at 300 DPI, but only about 132 × 170 px at 96 DPI — more than a 3× difference. Print and passport specs generally assume 300 DPI; screen-only images often use 96.

ExactPic defaults to 300 DPI, lets you change it, and shows the resulting pixel dimensions before you export so you always know exactly what you will get.

Web-only forms may say '600×600 pixels' or '250×250 max'. Use pixel mode and optionally add a KB target if both are required.