Would your profile photo survive the feed?
LinkedIn shows your photo as a 400px circle on your profile and a 40px one in the feed, and a picture that reads fine large can turn into a grey smudge small. This measures the things that decide it - resolution, exposure, focus, background - and shows you all three sizes at once.
Runs entirely in your browser - the image never leaves your device and nothing is uploaded to us.
The three sizes that matter
LinkedIn shows your photo as roughly a 400px circle on your profile, about 64px in search results and connection lists, and around 40px beside every comment and post in the feed. Almost all the impressions are the small ones. A photo chosen while looking at it full-screen tends to fail at 40px, which is why the tool shows all three.
What each measurement is
- Resolution - checked against LinkedIn's published 400 × 400 minimum and 8 MB file limit.
- Brightness - the average luminance of every pixel, 0 to 255. Faces get lost below about 90.
- Contrast spread - how far pixels vary from that average. A low number means flat light; a very high one means hard sun or flash.
- Sharpness - the variance of the Laplacian, the standard cheap focus measure. It is read from the sharpest part of the frame rather than averaged across the whole thing, so a deliberately blurred background counts in your favour rather than against you.
- Background activity - average edge strength around the outside of the frame, which is where the background lives in a headshot.
Dating mode
Switch the mode at the top and the same measurements are judged against a dating profile instead of a LinkedIn circle: a vertical card seen full-screen, a square grid tile, a small chat avatar. The thresholds move with it. A card needs more pixels than a 400px circle, portrait beats square, your face can sit much smaller in the frame, a second face stops being a warning and becomes a reason to use this photo later in the set - and a busy background stops being a fault, because on a dating profile where you are says something about you.
The frames are labelled generically - profile card, grid tile, chat avatar - on purpose. Tinder, Hinge and Bumble do not publish the pixel dimensions of their cards, so any number here would be a guess. Their written rules about photos, which they do publish, are covered in what the dating apps actually say about AI photos.
Why face framing is only sometimes checked
Face detection only runs where the browser provides it natively - Chrome and Edge do, Safari and Firefox do not. Rather than guessing at a face from skin tones and getting it wrong on a third of photos, the tool says it cannot measure it and draws a framing guide over the preview instead. Your head should roughly fill the dashed oval.
The things no checker can score
Whether you look approachable, whether the clothing matches the job you want next, whether the photo is five years old. Those decide more than any of the numbers above. A useful test: shrink it to 40px, look away, look back, and see whether you recognise yourself before you recognise the shirt.
If the answer is that the photo is fine but the light was never going to work, that is what generated headshots are for - and this is how to avoid the plastic look most of them have.
A photo can pass every check and still look like a photo of you at your desk.
Phoxel turns three phone shots into a studio-lit headshot on a clean background - the same set your colleagues paid a photographer for. From $6.