Why does 35 × 45 mm sometimes appear as 413 × 531 and sometimes as 413 × 532?

45 mm at 300 DPI is 531.5 pixels, so tools round it either way. Both are within a fraction of a millimetre and print the same.

Can FitKB check that my photo meets passport rules?

No. FitKB sets the shape, pixel size and file size. It does not check head size, background or expression, which are judged by the issuing authority.

Photo ID

Passport Photo Size in Pixels: mm, Inches and DPI Explained

By FitKB · Updated November 11, 2026 · 3 min read

Quick answer

Multiply each side in inches by the DPI, or each side in millimetres by the DPI and divide by 25.4. At 300 DPI, 35 × 45 mm is 413 × 531 pixels and 2 × 2 inches is 600 × 600 pixels. The issuing authority's rules always take priority over general guides.

Open the Passport Size Photo Maker 35x45mm tool

The conversion formula

DPI, dots per inch, says how many pixels are printed in each inch of paper. An inch is exactly 25.4 mm. To find the pixels needed for a printed size:

From inches: pixels = inches × DPI.
From millimetres: pixels = millimetres ÷ 25.4 × DPI.

300 DPI is the usual standard for photo prints. For example, 35 mm ÷ 25.4 × 300 = 413.4, so a 35 mm wide photo needs about 413 pixels across.

Common photo sizes at 300 DPI

Common passport and visa photo sizes converted to pixels at 300 DPI
Print size	Pixels at 300 DPI	Examples of use
35 × 45 mm	413 × 531 px	UK passports, Schengen visas, many other countries
2 × 2 in (51 × 51 mm)	600 × 600 px	US passports and visas
50 × 70 mm	591 × 827 px	Canadian passports
33 × 48 mm	390 × 567 px	Some Chinese visa applications

Requirements change and differ between print and online applications. Always confirm the size, file format and file size on the official website of the authority you are applying to.

Digital uploads are different from prints

Online applications usually state a size in pixels and a file size in KB, not millimetres. A printed size only matters when you print the photo. If a form asks for at least 600 × 600 pixels and at most 240 KB, those two numbers are all you need to meet.

The DPI value stored inside a file does not change how the photo looks on screen or its file size. Pixels are what count. See DPI vs pixels for more.

Making the photo

Stand in front of a plain, light wall in even daylight, without shadows on your face or behind you.
Ask someone to take the photo from about 1.5 m away at eye level, with your head and shoulders in the frame.
Open the 35 × 45 mm preset or the 2 × 2 inch preset.
Move the Vertical framing slider so your head is centred with space above it.
Set the KB limit from the form and download the result.

Printing the photo yourself

If you need a printed photo, most photo printing services accept a JPG and print it at a standard size such as 4 × 6 inches (10 × 15 cm). Place several copies of your passport photo on a 4 × 6 inch canvas at 300 DPI, which is 1200 × 1800 pixels, so each one prints at the right physical size. Check that the print service does not crop or scale the image to fit the paper.

Print on glossy or matte photo paper, not on plain office paper, and cut along the edges carefully. Many authorities reject photos that are damaged, creased or printed on ordinary paper.

Checklist before you submit

The pixel size or print size matches the official requirement exactly.
The file size and format match the online form, for example JPG under 240 KB.
Your face is in focus, with even lighting and no shadows on the face or background.
The background is plain and the colour the authority asks for.
Your head is straight, centred and the size the rules require.
The photo is recent, usually taken within the last six months.

FitKB handles the first two points. The rest depend on how the photo was taken, so retake it if any of them are not met.

Questions people also ask

Why does 35 × 45 mm sometimes appear as 413 × 531 and sometimes as 413 × 532?: 45 mm at 300 DPI is 531.5 pixels, so tools round it either way. Both are within a fraction of a millimetre and print the same.
Can FitKB check that my photo meets passport rules?: No. FitKB sets the shape, pixel size and file size. It does not check head size, background or expression, which are judged by the issuing authority.