The file name is not the file format
Renaming a photo converts nothing. The extension is a label your operating system uses to pick which app opens the file; the format is what the first bytes inside say it is, and an upload validator reads the bytes — which is why a file that opens perfectly on your laptop can still be refused.
You can read those bytes yourself. Open the photo in a plain text editor and look at the start of the first line — most of it is unreadable, and the first few characters are the file naming its own format:
| A JPEG | Hex FF D8 FF, usually shown as "ÿØÿ", then "JFIF" or "Exif". This is the JPEG the upload takes. |
|---|---|
| A PNG | The letters "PNG", after one unprintable character. |
| A HEIC from an iPhone | "ftyp" followed by "heic", "heix" or "mif1", a few bytes in. |
| A WebP | "RIFF" at the very start, then "WEBP" a few characters later. |
| A renamed file | Unchanged — renaming rewrites the label, never the bytes. A photo.jpg beginning "ftypheic" is a HEIC wearing the wrong name. |
The name matters for one other reason. An accented letter, an emoji, or two extensions stacked up — photo.heic.jpg — can produce a name a form cannot store, and that lands before the picture is looked at. Keep it plain: letters, digits and hyphens, one dot.
HEIC: the iPhone default that is not a JPEG
HEIC is what iPhones have shot by default for years. It stores the same picture in less space than a JPEG does, which helps nothing at a form that takes one container.
It also becomes a JPEG on its own, silently, depending on how the photo leaves the phone. AirDrop to a Mac hands over the original HEIC; Settings → Photos → "Transfer to Mac or PC" converts on one setting and not the other; a mail app commonly converts on the way out. Which route a file took is not visible in the picture, so "it worked last time" proves nothing.
- Stop it at the source: on an iPhone, Settings → Camera → Formats. "High Efficiency" shoots HEIC; "Most Compatible" shoots a JPEG.
- Export a photo you already have instead of renaming it. On a Mac, Preview → File → Export, format JPEG. On Windows, Paint → Save as → JPEG picture; Windows may ask to install its HEIF extension first, which is what lets it read the file at all.
- Verify the copy, not the original: reopen it in a text editor and confirm it starts with the JPEG bytes and not "ftyp".
- Then check it is still 600×600 to 1200×1200 pixels, square and inside 240 KB or smaller. Exporting rewrites the file size, and some converters resize while they are at it, so measure the copy and never the original.
PNG, WebP and screenshots
These are not exotic mistakes — they are what ordinary instincts produce, and each fails for its own reason:
- PNG is lossless, which sounds like the better choice and is the worse one here: the same photograph is several times the size of the equivalent JPEG, and the cap is on the file, not the picture.
- PNG also carries an alpha channel — transparency — and converters disagree about it: some flatten it onto white, some onto black. A photo whose background was removed and saved as a transparent PNG can arrive with a solid black background, having looked correct in every preview.
- WebP is what many sites now serve, so "save image as" in a browser often produces one. Your computer opens it happily, which tells you what your computer supports and nothing else.
- A screenshot is a picture of your screen, not a copy of your photo: a PNG at whatever size the screen displayed, re-rendered through display scaling. It fails on shape, and usually sharpness, before anyone looks at the face.
Colour: greyscale, Display-P3 and the skin-tone shift
Two colour problems fail photographs, and they have nothing to do with each other.
The first is blunt, and worth sourcing precisely. Neither standard we can quote in full is the DS-160 instruction sheet — 8 FAM 402.1 is the State Department's adjudication manual for passport photographs, GOV.UK's list is for UK passports — and both are unambiguous. The manual spends six words on it: "The photograph must be in color". GOV.UK asks a digital photo to be "in colour". Nobody submits greyscale on purpose; it arrives from a filter left on, or a scanner set to black and white.
The second costs people a retake they did not need. Recent iPhones and Android flagships capture in Display-P3, wider than the sRGB most software assumes, and the file carries a tag naming which space its numbers belong to. Strip that tag without converting the numbers — which "export for web" and many converters do — and the same numbers get read as sRGB. Saturated colours shift, and skin is a saturated colour.
The manual describes that outcome without naming its cause: "Brightness and contrast should accurately reproduce subject’s natural skin tones. Photographs without proper contrast and color may obscure unique facial features and cause problems in printing, resulting in off-colored facial features (purple/yellow)." Export to sRGB explicitly wherever the option exists, and re-export anything that has been through print or layout software, which can hand the file back in CMYK rather than RGB — a colour space built for ink, and one that swaps the channels a decoder is expecting.
EXIF orientation: the metadata your screen obeys
Phone cameras do not rotate photographs. They store the pixels the way the sensor read them and write a small orientation flag into the metadata saying which way up to show them. Your phone reads the flag and turns the picture for you.
Anything reading raw pixels does not have to. Ignore the flag and the photograph is a quarter-turn over: the frame is the wrong shape, the head sits against the side rather than the top, and every measurement from it is nonsense — while your copy stays upright on screen throughout.
It catches you a second way: some editors "rotate" by rewriting the flag rather than the pixels, so the picture looks turned and the file behaves as before. A re-export settles both, because a fresh copy writes the pixels as displayed and leaves the flag nothing to describe. What happens to the rest of the metadata is down to the exporter — some strip it, some copy the original EXIF across, including the GPS coordinates a phone attaches to a photo taken at home.
The file-size window, and what compression does to a face
The cap for a DS-160 photo is 240 KB or smaller, and it is the rule most often solved badly. Two levers are the ones people reach for: how many pixels the file holds, and how hard the encoder squeezes each one. A third, below, costs nothing. The whole spec, so the window sits in one place:
| Photo size | 600×600 to 1200×1200 pixels, square |
|---|---|
| File size | 240 KB or smaller |
| Format | JPEG |
| Head height | 50–69% of the photo's total height |
| Eye height | 56–69% up from the bottom of the photo |
| Background | Plain white or off-white |
Reach for the pixels first: coming down inside 600×600 to 1200×1200 pixels, square costs nothing that matters. Cutting quality instead damages the photograph, and the damage has a name — 8 FAM 402.1 says "Images composed of grain-like particles may not be acceptable. Photographs with visible pixels are not acceptable." Squeezing under a ceiling that way produces exactly that blocking around the eyes, mouth and hairline: the file passes the size rule by breaking the quality one.
There is an easier lever almost nobody mentions: the background. A JPEG spends its bits on detail, and a flat, evenly lit background has almost none to encode — so the same face shot against a bookshelf and against a plain wall can differ several times over in file size at identical dimensions and quality. If your file is stubbornly too big, the clutter behind you is usually why. That requirement reads: Plain white or off-white.
The UK publishes a floor as well as a ceiling: GOV.UK asks a digital passport photo to be "at least 50KB and no more than 10MB", so a file compressed too hard is refused for being too small. That same list names colour, focus and a pixel floor — and no file format at all.
What re-encoding does — including ours
Every conversion here re-encodes the picture, and JPEG is lossy: each save discards detail the previous save already thinned. One conversion from the original is invisible; five conversions of a file that has been emailed, screenshotted, cropped and re-saved are not. Convert once, from the original.
Re-encoding is not editing, and the manual is careful about which is which. 8 FAM 402.1 says "Digital manipulation and/or retouching of the facial image on photographs is not acceptable" and rules out beauty filters by name — while also saying plainly that "Computer-generated photographs are acceptable if the image is sharp and clear". Changing a container, a colour profile or an orientation flag alters no part of the face. A smoothing filter does.
Where we stand, because a guide that hides its conflict of interest is not worth citing: this service decodes your photograph, crops it, replaces the background and re-encodes the result. It does not retouch or reshape the face. We claim no acceptance anywhere — only that you see the file measured against every rule first.
One route settles it against us. GOV.UK requires a photo uploaded during a fully-online UK passport application to be "unaltered by computer software" and tells applicants "Do not crop your photo - it will be done for you". A cropped photograph with a replaced background does not meet that, so we do not claim ours for that route.
Check the file you already have
The composition rules are no easier to eyeball than the encoding ones — head size and eye height are bands, not impressions. These are the checks a DS-160 photo is held to here:
- Exactly one face, looking straight ahead
- Head sized 50–69% of frame
- Eyes at the required height (56–69% from the bottom)
- No head tilt
- Background replaced with pure white
- Even, uniform background
- Sharp focus — no blur
- Natural exposure — not too dark or bright
The check is free, needs no account, and reports what passed and what failed rule by rule. If it passes and you want the finished file, the output is 600×600 JPEG · under 240 KB · pure white background, with a print-ready 4×6 sheet (6 copies) for the stage where prints matter.
A failure on the file rather than the photograph is the good outcome: a container, a colour profile and an orientation flag are all fixable from the picture you have.
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