Exam portals check uploads with automatic scripts before a person ever sees them. A script doesn't know that 52 KB is "almost" 50 KB; it simply says no. Then, at document verification or at the exam centre, a person compares the photo with your face. Here are the reasons uploads fail at each stage, roughly in the order they happen.
1. The file is too big or too small
Every form gives a KB range, like 20–50 KB. A phone photo is usually 2–5 MB, a hundred times too big. Less obvious: files can also be too small. Railways asks for a 30–49 KB signature, so a 12 KB file fails.
Fix: compress to a target, not "as small as possible". ExamPic searches for the JPEG quality that lands inside the range, and pads the file if it's below the minimum.
2. Wrong pixel size or shape
A square selfie squeezed into a 200 × 230 box looks stretched. Some portals reject anything that isn't the exact size; others reject the wrong aspect ratio (GATE allows width ÷ height between 0.66 and 0.89).
Fix: crop to the right shape first, then resize. Never stretch.
3. Wrong format
Most portals accept only JPG/JPEG. iPhone photos are often HEIC, and screenshots are PNG.
Fix: save as JPG. ExamPic always outputs JPG.
4. The background isn't white
A wall that looks white to you photographs as grey, cream or blue, especially indoors at night. "Plain white background" is the single most broken rule.
Fix: stand in daylight in front of a plain light wall, then use "Replace background" to turn it pure white (or light grey for forms like OCI that don't want white).
5. The face is too small, too big or off-centre
UPSC wants the face to cover about 75% of the photo; GATE says 60–70%; NEET and JEE about 80%. A full-body or half-body photo fails all of them.
Fix: use a tool that frames by face size. ExamPic finds your face and zooms to each exam's rule, then shows the head size as a percentage.
6. Shadows, glare and dark faces
Light from one side puts half the face in shadow; a flash makes spectacles glare; a window behind you turns your face dark.
Fix: face the light source. Take spectacles off unless your exam allows them and you wear them daily.
7. Signature problems
Signatures in capital letters, faint pencil, blue ink where black is required, ruled paper, or a signature cut off at the edge are all common rejections. UPSC also requires three signatures in one image.
Fix: sign with a black pen on plain white paper, photograph from straight above, and let the tool clean the paper and crop with a margin.
8. The photo doesn't look like you today
Banks, NTA and UPSC match your uploaded photo against your face at the exam centre, sometimes biometrically. An old photo, heavy filters or a beauty app can fail that match.
Fix: take a fresh photo for each application cycle and keep the same file for every later stage.
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