The 600×750 photo — the pixel floor for the UK passport digital application.

The specification

The UK passport photo spec, digital and print

Both halves of the spec in one table — the digital floor and the print frame it sits next to. Verifiable at the official source linked at the bottom of this page:

Reading the rule

What “at least 600 x 750 pixels” means

Unlike the DV lottery's exactly-600×600 rule, the UK spec is a minimum: each side has its own floor. A photo 600 pixels wide but only 700 tall fails; one at 900 × 1100 passes the pixel rule. The published spec pairs that floor with a file-size window — 50 KB – 10 MB — wide enough that a phone camera original usually fits as-is.

Two practical consequences. First, do not shrink a good photo down to exactly 600×750 on principle — there is nothing to gain, and detail to lose. Second, do not stretch a small photo up to reach the floor: upscaling adds pixels, not detail, and the photo rules judge the picture, not just the ruler. Start from the original camera file, which on any modern phone is far above the minimum.

And pixels are the easy gate. The photo must also show your head at 64–76% of the photo's height (29–34 mm, crown to chin), eyes 50–68% up from the bottom of the photo, on a Plain light grey or cream — not white background — the composition rules that actually reject photos. The full rulebook lives on the UK passport photo requirements page.

The arithmetic

Is 600x750 just the 35x45 mm print in pixels? No — here is the math

The UK prints passport photos at 45 mm high by 35 mm wide, so it is natural to assume the digital minimum is that frame at some scan resolution. It is not, and the arithmetic proves it two ways:

• The shapes differ. 600:750 divides down to 4:5 (both by 150) — a ratio of 0.80. 35:45 divides down to 7:9 (both by 5) — about 0.78. Close, but not the same rectangle.
• No single resolution maps one to the other. 35 mm is about 1.38 inches, and 600 ÷ 1.38 ≈ 435 pixels per inch; 45 mm is about 1.77 inches, and 750 ÷ 1.77 ≈ 423 pixels per inch. If 600×750 were a scan of the print, those two numbers would match. They do not.

One more consequence worth knowing: a 35×45 print scanned at the common 300 DPI comes out at 413 × 531 pixels — under the floor on both sides. Scanned at 600 DPI it is 827 × 1063 pixels, which clears the floor comfortably. So the print and the upload are related but distinct specs, written independently — treat each on its own terms. The print size has its own page: the 35x45 mm photo.

Two routes, one document

The digital route vs the printed route

Which spec you must satisfy depends on how you apply. The printed route takes a 45 mm × 35 mm photo with the head at 29–34 mm crown to chin. The digital route takes a file of at least 600 × 750 pixels, 50 KB – 10 MB. What the two share is everything except the frame: a plain light-grey or cream background — not white — and a photo taken within the last month.

One honest note about the fully-digital path: if you apply online and photograph yourself on your device, GOV.UK crops the image for you and asks you not to pre-crop. So the job is not hitting an exact pixel count — it is producing a photo that meets the composition rules, at or above the floor. A finished compliant photo serves the printed route directly, and works as your compliant reference for background, size and expression on the digital one.

That one-month clock deserves repeating, because it is the quiet spec-killer: most countries accept a six-month-old photo, the UK does not. Whatever you have on file from a previous application is out of date by rule, regardless of its pixels.

Meeting it

Getting a photo that clears 600x750 — and the rest

Any phone camera clears the pixel floor. What a phone photo does not arrive with is the rest of the spec: the plain light-grey background HM Passport Office requires, the head sized to 64–76% of the photo's height (29–34 mm, crown to chin), the eyes inside their band. That is the work the UK flow here does server-side from one upload — background replaced with the required grey, crop solved so the head lands in the band, and the output delivered as 35×45 mm JPEG at 600 dpi · plain light-grey background — 827 × 1063 pixels, over the digital floor on both sides, plus a print-ready sheet for the paper route. To be honest about the limits: this is not a general resizer — it produces the fixed sizes governments publish, the UK spec among them, not arbitrary dimensions.

Already have a photo you think complies? The free UK passport photo checker measures it against the spec exactly as-is and alters nothing. And if the UK is not your destination, every country's frame and pixel window is on the passport photo size chart.

Questions

Fair questions, straight answers.