A standard U.S. passport photo is 2 x 2 inches , which is 51 x 51 mm and has a square 1:1 ratio.

Basic size in different units

  • Inches: 2 x 2 inches.
  • Millimeters: 51 x 51 mm.
  • Centimeters: 5.1 x 5.1 cm.

Face and digital requirements (U.S.)

  • The head height (chin to top of head) must be about 1 to 1⅜ inches (25–35 mm).
  • Digital photos are usually 600 x 600 pixels (up to about 1200 x 1200) with a square aspect ratio.

Other countries (quick note)

  • UK passport photos are typically 35 x 45 mm (about 1.37 x 1.77 inches), portrait‑oriented.
  • Always check your country’s official passport office site, as sizes and rules can differ.

Information gathered from public forums or data available on the internet and portrayed here.