What "Passport Size Photo" Means When a Form Gives No Size

Passports were the first document most people needed a standardized photo for, so the passport photo became the default small portrait. When a school, bank, employer, exam board or club needs a photo for a file or a card, it rarely writes its own specification. It asks for a passport size photo, because everyone can get one at a booth, a pharmacy or a photo shop, and because the photo shops already have the size set up. The phrase is a shortcut that assumes you and the form share the same local idea of what a passport photo is.

That assumption breaks when the form travels. A UK university and an Indian exam board both mean 35 × 45 mm, because that is the passport size in both countries according to GOV.UK's printed photo rules and India's passport instruction booklet, which describes a 4.5 cm by 3.5 cm photo. A US employer means the 2 × 2 inch square on the State Department's photo page. A Canadian office might picture the much larger 50 × 70 mm print that Canada uses for passports. The words are the same; the size behind them depends on where the form was written.

So the first job is not to measure anything. It is to work out which country's idea of passport size the form is borrowing. Usually that is simply the country of the institution: an Indian university, a German employer or a Kenyan exam board will expect the local passport size. It gets harder with international forms, such as a scholarship run from abroad or a multinational's job portal, where the writer may live in one country and the applicants in many. For those, the clues in the form itself, covered below, matter more than the address at the top of the page.

In the UK, India, the Schengen area and many other countries, a passport size photo is 35 × 45 mm or very close to it. The Schengen countries' consulates ask for that size too; the Czech foreign ministry's visa photo page, for example, lists 35 × 45 mm. It is the size most official pages name, and it is the one photo shops and booths are most likely to have preset. If you cannot tell where a form comes from, 35 × 45 mm is the reading most likely to be accepted.

The United States is the main exception, with its 2 × 2 inch square, and forms written there use the same square when they say passport size. Canada uses 50 × 70 mm for passports, according to Canada's passport photo page, so a Canadian form that says passport size may expect a larger print than you would guess. China's visa photo is 33 × 48 mm, slightly taller and narrower than the common size. The table below lists these sizes with the official page for each, so you can check the one that matches your form. The overview of passport photo sizes grouped by country goes through the families in more detail.

Forms that do not state a size often give it away in other ways. On paper, the most reliable clue is the box marked for the photo. Many forms draw it to scale, so a ruler tells you the size directly; India's booklet, for instance, says the photo should fit within the box provided. If the box measures about 3.5 by 4.5 cm, you have your answer. If it is square and about 5 cm on each side, the form expects the US size. A box that is clearly larger or smaller than any photo is usually just a placeholder, and then the other clues matter more.

On an online form, look at the upload field and the error messages. A note such as "JPG, 200 × 230 px, under 50 KB" tells you everything a size in centimeters would and more. Some portals show the limits only after a failed upload, so a test upload with any photo can reveal them. The help pages, the FAQ and the printed instructions that come with an exam or job application often state the size in a footnote even when the form field does not. The list below collects the clues in the order worth checking.

When the clues disagree, follow the most specific one. A pixel size in an upload field beats a vague "passport size" in the instructions, and a box drawn to scale beats both for a paper form. If nothing is specific, a 35 × 45 mm photo with a little margin around the head is the reading that fails least often, because it fits most boxes and can be trimmed to a square if needed.

A size in centimeters or inches describes paper. An online form stores pixels. To move between them you need a resolution, the number of pixels per inch, and photo printing has long used 300. One inch is exactly 25.4 mm, as NIST's length units page states, so at 300 dpi one millimeter is about 11.8 pixels. A 35 × 45 mm photo is therefore 413 × 531 pixels, and a 2 × 2 inch photo is exactly 600 × 600. The US State Department uses the same arithmetic when it tells visa applicants to scan a 2 × 2 inch print at 300 pixels per inch on its digital image requirements.

If the form names pixels, use them and ignore the centimeters. If it names only centimeters, 300 dpi is a safe resolution for a file that might also be printed, while 200 dpi gives a smaller file that still looks sharp on screen. The pixel converter page does the sum for any size and resolution, and the px to cm converter works the other way when a form gives pixels and you want to know how large the photo will print. To produce the file itself, resize the image to centimeters: type the size in cm, leave the DPI at 300, and choose Crop to fill so the photo is trimmed to the right shape rather than stretched.

Pixel size and file size are separate limits, and many forms set both. Pixels decide how large the picture is; kilobytes decide how much data the file holds, which depends on the format and the compression. Official portals show how wide the range can be. US visa portals take at most 240 KB for a 600 to 1200 pixel square, according to the State Department's digital image rules, while GOV.UK's digital photo rules accept anything from 50 KB to 10 MB at no less than 600 × 750 pixels. Job and exam portals tend to sit at the strict end, and some set a minimum as well as a maximum so that blank or broken files are refused.

The order of work matters. Crop and resize to the right pixel size first, then compress to the KB limit, because resizing after compressing throws away the careful compression and usually produces a larger file again. A photo at 413 × 531 pixels saved as JPG is normally well under 100 KB already, so a strict limit needs only light compression. A very low limit, on the other hand, is a sign that the form expects a small pixel size too; squeezing a full-resolution phone photo into a few dozen KB by compression alone leaves blocky skin and smeared edges, while a smaller, properly resized file at the same KB stays clean. The guide to reducing image size in KB covers the limits forms use for photos, signatures and scans.

Paper forms often want two or more identical photos, and printing them one at a time wastes paper. Photo shops print passport photos in sets on a single sheet, and you can do the same at home or at a kiosk by laying several copies on one standard print. A 4 × 6 inch print, the most common photo size, holds six 2 × 2 inch photos or six 35 × 45 mm photos with room to cut; an A4 page holds more. Print at actual size, not "fit to page", or every copy will come out slightly too small or too large.

The passport size photo maker is set up for this. It crops your portrait to 35 × 45 mm, lets you change the Background, and lays out eight copies on an A4 sheet with cut lines, or a 4 × 6 inch sheet if you prefer. If a passport office will see the photo, check its printing rules too: India's booklet refuses computer prints and asks for good-quality photo paper, so for a passport application a print from a photo lab is the safer route. For a job or school form, a home print on photo paper is usually fine, but let the ink dry fully before you cut and glue the photo, or it will smudge on the form.