ID Photo Size Calculator
Convert a photo size between millimeters and pixels at 150, 300, or 600 DPI. Passport and visa specs are usually printed at 300 DPI.
Millimeters to pixels
Pixels at 300 DPI
413 × 531 px
Millimeters at 300 DPI
Enter a pixel size to convert.
Common ID photo sizes
| Photo | Size | Pixels (300 DPI) | Used for |
|---|---|---|---|
| 35x45mm Photo | 35×45 mm | 413×531 px | UK and Australia passports |
| 2x2 Photo | 51×51 mm | 600×600 px | United States |
| 33x48mm Photo | 33×48 mm | 390×567 px | China visa applications |
| 35x40mm Photo | 35×40 mm | 413×472 px | National ID cards |
| 30x40mm Photo | 30×40 mm | 354×472 px | Work permits |
| 45x35mm Photo | 45×35 mm | 531×413 px | Horizontal ID cards |
| 1x1 Photo | 25.4×25.4 mm | 300×300 px | Government ID cards |
| Philippines Passport Photo | 35×45 mm | 413×531 px | Philippines |
| Malaysia Passport Photo | 35×50 mm | 413×591 px | Malaysia |
| Turkey Passport Photo | 50×60 mm | 591×709 px | Turkey |
How DPI changes the pixel size
The physical size of an ID photo is fixed in millimetres — what changes with DPI is how many pixels fill that space. To convert by hand, divide the millimetre value by 25.4 to get inches, then multiply by the DPI. For 35 mm at 300 DPI: 35 / 25.4 × 300 = 413 pixels.
The table below shows the same 35x45 mm photo at each resolution. All three print at exactly 35x45 mm; only the sharpness differs.
| Resolution | 35 × 45 mm in pixels | Notes |
|---|---|---|
| 150 DPI | 207 × 266 px | Below the usual minimum — prints visibly soft |
| 300 DPI | 413 × 531 px | The standard for printed passport and visa photos |
| 600 DPI | 827 × 1063 px | Higher-resolution option, same 35x45 mm print size |
Photo size and resolution questions
What is DPI and why does it matter for an ID photo?▾
DPI (dots per inch) is the resolution a photo is printed at. It decides how many pixels make up each inch of the physical photo: 300 DPI means 300 pixels per inch. A higher DPI gives a sharper print of the same physical size — it does not make the photo physically larger.
How do I convert millimetres to pixels?▾
Divide the millimetre value by 25.4 to get inches, then multiply by the DPI. For 35 mm at 300 DPI: 35 / 25.4 × 300 = 413 pixels. The calculator above does this for both dimensions at once.
What DPI should I use for a passport photo?▾
300 DPI is the standard and is accepted almost everywhere. Use 600 DPI only if an application explicitly asks for a high-resolution file. Some online forms skip DPI entirely and just state a pixel size — match that number directly instead.
Does a higher DPI make my printed photo bigger?▾
No. A 35x45 mm photo is 35x45 mm whether it is 300 DPI or 600 DPI. The higher DPI only packs more pixels into the same physical space, which makes the print sharper. Print size is set in millimetres or inches; DPI only affects detail.
Why does my application form ask for pixels instead of millimetres?▾
Online forms check the uploaded file programmatically, and a file is measured in pixels. When a form gives you a pixel size, enter it directly rather than converting — the two are independent of DPI once the file exists.
What is 35x45 mm in pixels?▾
413 × 531 pixels at 300 DPI, which is the standard resolution. At 600 DPI it is 827 × 1063 pixels, and at 150 DPI it is 207 × 266 pixels.
Need a photo in one of these sizes?
Open the ID photo maker with the spec preloaded, upload a photo, and download the result.
Make an ID photo