Print dimensions describe the photograph on paper
Inches and millimeters tell you the finished width and height. A 2 × 2 inch photo is square; a 35 × 45 mm photo is taller than it is wide. Changing between those shapes affects how much of the head and shoulders fits.
Choose the size specified for your document rather than the nearest familiar format. Similar dimensions do not imply the same rules for head position or who may take the photograph.
Pixel dimensions describe the digital image
A 600 × 600 pixel file contains 600 pixels across and 600 down. Cropping changes which part of the picture remains; resizing changes the number of pixels used to represent it.
Increasing a small image to a larger pixel count does not recreate detail lost in the original. Start with the camera file instead of enlarging a thumbnail, screenshot or preview.
File size is a separate limit
Kilobytes and megabytes measure the storage used by the file. Two images with the same pixel dimensions can have different file sizes because of their content, format and compression.
Check the accepted format as well as the size limit. Exporting a JPEG copy is different from renaming a PNG file. If compression is needed, inspect the exported image for lost detail rather than repeatedly saving an already compressed copy.
Resolution connects pixels to print size
Multiply the printed width in inches by the pixels per inch to find the pixel width. For example, a 2-inch square at 300 pixels per inch uses 600 × 600 pixels. This is a print calculation, not a universal application requirement.
The printer still needs to use the intended scale. Turn off fit-to-page and measure the finished portrait, since changing print settings can change its physical dimensions.
The face must fit the specification too
A correctly sized file or print can still contain a head that is too large, too small or poorly positioned. Check the document’s head-height and eye-position instructions alongside the outer dimensions.
Inspect an automatic crop before using it. If the application requests an uncropped original, retain that original and follow its upload process instead of preparing a tighter frame.
Sources and further reading
US Department of State · Passport photos ↗HM Passport Office · Printed photos ↗Requirements can change. Check the official instructions for your application before submitting.
Merodim is an independent photo-preparation service, not a government agency. Find your document →
