Singapore's immigration authority gives passport photo specifications in two places: one in pixels for digital uploads, the other in millimetres for prints. The two documents never refer to each other, leaving applicants to do the arithmetic themselves.
This guide reconciles the two sets of figures.
What each document actually says
The authority's photo guidelines page gives only digital figures. The recommended size for uploading through its e-services is 400 × 514 pixels, the maximum file size is 8 MB, and the accepted formats are JPG, JPEG, HEIC, HEIF and PNG. The page says the specification is based on the standards of the International Organization for Standardization and the International Civil Aviation Organization, without naming a document.
It gives no millimetre figures at all. Those are in a different document — the current application form for a passport applied for overseas — which specifies a photo 35 mm wide by 45 mm high, with the face measuring between 25 mm and 35 mm from chin to crown.
Two specifications, in two documents, in two units, for one photo.
Joining them
If the 400 × 514 pixel file is meant to be the 35 × 45 mm print, the resolution follows directly. An inch is 25.4 mm, so 35 mm is 1.378 inches, and 400 pixels across that is 290.3 pixels per inch. Down the height, 514 pixels across 45 mm gives 290.1.
So the two specifications, if they describe the same image, imply about 290 pixels per inch. That is our derivation, not the authority's. It is also slightly below the 300 pixels per inch that the aviation organisation's own passport standard says a printed photo should survive being scanned at.
The proportions agree more closely than the resolution suggests. The print, 35 by 45, is exactly 7:9 — the ratio the aviation standard gives as typical. The pixel dimensions are 400 by 514, which is 0.77821 against 7:9's 0.77778. A true 7:9 at 400 pixels wide would be 514.29 pixels tall. The authority rounded it. The figures match to within a fraction of a pixel — close enough to suggest intent, but far enough apart to show they weren't derived from a single internal source.
The head, in pixels
The form's 25 to 35 mm chin-to-crown range is a proportion of a 45 mm-high print. Worked out, it is 55.6% to 77.8% of the photo's height.
Carried into the upload file, that is a head between about 286 and 400 pixels tall in a 514-pixel image. That is the figure to aim for when cropping, and it is not written down anywhere by the authority.
The rule everyone quotes, which is for a different photo
The most widely repeated instruction for passport photos is that the face should fill 70 to 80 per cent of the frame. It appears on countless photo-service sites as though it were the rule. The authority does not say it.
It comes from the aviation organisation's passport standard, and in that standard it governs something else: the portrait printed inside the passport, on the data page. The standard's own wording ties the 70 to 80 per cent to the zone of the document where that printed portrait sits. It is an instruction to the passport printer, not to the person submitting a photo.
Applied to the submitted photo anyway, it produces a conflict. Seventy to eighty per cent of a 45 mm height is a head of 31.5 to 36 mm. At its upper end, the 70-to-80-per-cent rule implies a 36 mm head, which is larger than the authority's own stated maximum of 35 mm.
File sizes that no longer apply
Several file-size limits circulate for Singapore photos, and most are out of date.
60 KB was a real limit, for one scheme, a long time ago. A 2005 announcement launching the APEC Business Travel Card asked for a photo of no more than 60 KB. The current page for that card uses the 60 KB figure only for a scanned signature; for the photo, it refers to the general guidelines.
150 KB was the limit on an earlier passport e-service, since retired. An archived copy of its page from 2016 is the only trace.
The current limit is the 8 MB on the guidelines page.
The same archived page is also the only place the authority ever joined the two specifications, telling users to resize their image to 400 × 514 pixels. It came with a cropping tool on the authority's online services. That tool's address no longer resolves.
The neighbours, and one widely misattributed size
Malaysia's own guide for its online passport service asks for a white background and a JPEG between 100 and 300 KB. It gives no pixel or millimetre dimensions.
A set of Malaysian figures does circulate widely as the passport specification — 35 × 50 mm, with a 30 to 35 mm head and a 25 KB limit. They are genuine, and they come from an official Malaysian immigration document, but that document covers visit-pass applications by foreigners. They are not the requirements for a Malaysian passport.
The Philippines and Indonesia take the photo at the appointment, so neither publishes a size for applicants to meet.
What to do with a phone photo
Crop to 7:9. Scale to 400 × 514 pixels. The head, from chin to crown, should be 286 to 400 pixels tall; this means it fills a little more than half the frame's height, not most of it. Keep the file under 8 MB, which at this size is not a real constraint. If you are printing, 35 × 45 mm at about 290 pixels per inch is what those pixels become.
And ignore instructions to make the face fill 70 to 80 per cent of the frame. That rule is for the passport printer, and following it too closely can take a photo past the limit the authority sets.
What each figure rests on
Sources for the authority's figures are its photo guidelines page (updated 28 April 2026) for pixels and its overseas passport form for millimetres. The historical 60 KB and 150 KB limits were found in a 2005 media release and an archived e-service page. The 70 to 80 per cent rule, 7:9 ratio, and 300 pixels-per-inch scanning figure are from ICAO Doc 9303, Part 3. Our own computations (21 September 2026) produced the resolution, the pixel-based head size, and the 36 mm conflict.
The aviation standard was read from an archived copy, because its publisher's site refused direct access. Before relying on its exact wording, check that a newer edition has not superseded the eighth.
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