Stamp-Size Photo (32×45 mm) — Size, Uses and Limits

What Is a Stamp-Size Photo and How Does It Differ?

A stamp-size photo is the trade name for the small **32 × 45 mm** format. The name comes from its resemblance to a postage stamp; no regulation defines it, and no institution is obliged to use the phrase on its form. That makes the name a slipperier piece of information than the measurement itself: from one studio to the next, values other than 3.2 × 4.5 cm may be meant by it.

What separates it from a normal ID photo is not only size but purpose. 35 × 45 mm carries the international standard, 50 × 60 mm is Turkey's official biometric size, and 45 × 60 mm is the classic format of institutional files. The stamp size replaces none of them; it covers the small photo glued to a form rather than printed onto a document. For the complete list of sizes, the table of all document photo sizes is the single reference.

How Many Pixels Is 32 × 45 mm? (378 × 531 px)

The conversion uses the same formula at every size: divide the millimetres by 25.4 and multiply by the DPI. 32 ÷ 25.4 × 300 = 377.95 → **378 pixels**, and 45 ÷ 25.4 × 300 = 531.49 → **531 pixels**. At 600 DPI the same size becomes 756 × 1063 pixels. The gap between two rows of the table is sometimes a single millimetre, yet it changes the outcome entirely: 3.2 × 4.5 and 3.5 × 4.5 share the same height and differ only by 3 mm in width — and those 3 mm are the sole reason one is internationally valid and the other is not.

That is also why you cannot scale a 35 × 45 photo into 32 × 45: scaling preserves the ratio, so bringing the width down to 32 also drops the height to 41 mm. The correct operation is to reframe — trim from the sides and re-centre the head. Institutions with digital forms never ask about millimetres at all; their system looks straight at the pixel dimensions and the kilobyte size. That distinction is worked through with concrete institutional examples on the student ID and enrolment photo page.

Which Procedures Ask for the Small Format?

The small format shows up wherever the photo is not printed onto a document but attached to a form or a file: membership and enrolment paperwork, internal staff files, archive forms, and the annex pages of course or programme applications. What they share is that the photo serves as a file record rather than an identity verification instrument, so the size tolerance is looser than for biometric documents. Looser does not mean arbitrary, though: quantity, background colour and size always follow the institution's own notice.

In practice the most common problem is a form that says only "stamp photo". Filling in such a form, the one correct move is to ask for the millimetres; guessing the size means paying for the print twice. Procedures that print the photo onto a card sit outside this group — the Passolig card, for instance, imposes its own size and background rules, and the private security ID card application asks for the size stated in its own notice.

Why Can It Not Be Used for an ID Card, Passport or Licence?

The biometric photo guidance of Turkey's Directorate General of Population and Citizenship Affairs defines a single size for the ID card, passport and driving licence: **50 × 60 mm**, white or light grey shadow-free background, **32-36 mm head height** and a neutral expression. That head-height band alone explains why the stamp size fails on these documents: the frame is 32 mm wide, exactly the lower bound of the required head height. Once the face is at the correct scale, the width of the head no longer fits the frame.

The same limit applies internationally. ICAO Doc 9303 defines a 35 × 45 mm carrier for machine readable travel documents; 32 mm sits below that value and automated face checks find the framing margin insufficient. In short, the stamp size is accepted neither in ID card procedures nor in visa applications. You can check which size applies to which document on the biometric photo sizes by document in Turkey page, and find the full rule set for the card application on the Turkish ID card photo page.

Is Saying "Stamp-Size" to a Photographer Enough?

It is not. Because the name is unofficial, it has no shared meaning at the counter either; some studios mean 3.2 × 4.5 cm, others something smaller still. A sheet printed at the wrong size is money that cannot be recovered. The safe sentence is: "3.2 by 4.5 centimetres, white background, this many copies." If the institution states a different size, follow that — this page clarifies what the name refers to; it does not override the institution's request.

Once the size is confirmed, the whole flow fits into one shot. Upload the photo; the AI checks background, expression, sharpness and framing on separate lines, then rebuilds the 32 × 45 mm frame. Because a 10 × 15 photo sheet actually measures 101.6 × 152.4 mm, three columns take 96 mm and three rows 135 mm — a geometric capacity of nine photos, with the final layout after cutting tolerance shown on the order screen. If you also need a larger size such as 45 × 60 mm, preparing both together removes the problem of two different faces shot on two different days.