SIZE EXPLAINER

Visa photo millimetres, pixels and DPI are not the same thing

Photos are processed in your browser. They are never uploaded to any server.

Millimetres describe paper. Pixels describe a digital image. DPI or ppi connects the two only when you print. A 600 × 600 file has no fixed physical size until a printer scale is chosen.

Choose the exact visa photo preset

Use the unit from the application route

If a portal asks for 600 × 600 pixels, follow the digital rule. If an embassy asks for a 35 × 45 mm paper photo, follow the physical rule. Do not convert one into the other unless you need to create a print file or scan a paper copy.

The country name is not enough. The United States digital visa image has a pixel range, while a requested paper photo is 2 × 2 inches. The UK digital route in this tool gives a minimum of 600 × 750 pixels and no millimetre size.

The 300 ppi conversion

Visa Photo Prep uses 300 pixels per inch for print exports when an official paper source gives millimetres but no pixel size. The calculation is:

pixels = millimetres ÷ 25.4 × 300

Round to the nearest whole pixel. Using that rule:

• 35 × 45 mm becomes about 413 × 531 pixels.
• 33 × 48 mm becomes about 390 × 567 pixels.
• 50.8 × 50.8 mm, exactly 2 × 2 inches, becomes 600 × 600 pixels.

These numbers describe this site's 300 ppi print masters. They do not turn into official digital upload rules unless the authority says so.

Why 51 mm and 2 inches are both used for a U.S. photo

Two inches equals 50.8 mm. The U.S. source rounds that physical value to 51 mm. For the tool's print output, 2 inches at 300 ppi is exactly 600 pixels.

That arithmetic does not mean every 600 × 600 image will print at 2 × 2 inches. If a printer fits it to a different page area, the physical copy changes size.

Why changing DPI metadata may change nothing

A file can remain 600 × 600 pixels whether its metadata says 72, 96 or 300 ppi. On screen, the pixel grid is still the same. The metadata only helps software choose a physical print size.

Some print services ignore it and fill the selected paper. That is why the 4 × 6 guide tells you to choose actual size, turn off automatic fitting and measure a printed copy.

Do not resize by stretching

A 35:45 photo has a 7:9 aspect ratio. A U.S. visa image is square. Typing a new width and height into a generic resizer can pull the face wider or taller to fill the frame.

Crop to the required ratio first. Keep the head in the official range. Resize only after the crop is correct.

Choose the right check

1. For an online upload, inspect pixel dimensions, file type, file size and the photograph itself.
2. For a paper submission, inspect the crop, print scale and final millimetres with a ruler.
3. For a scanned paper photo, follow the authority's scanning resolution and digital limits.

For the actual print workflow, read how to print visa photos on a 4 × 6 sheet.

Conversions use 25.4 mm per inch and this site's 300 ppi print setting. Official document sources remain authoritative for required sizes.