See halos before your buyers do.

Drop in a PNG and check it the way it will actually be used — on pure black, pure white, and a checkerboard. White fringes, leftover background corners, and clipped edges show up instantly.

Drop PNG files here, or tap to choose

PNG works best. WebP and JPG are checked too — JPG has no transparency, and this will tell you so.
You can drop several files at once and switch between them below.

Choose files

Files stay on this device — everything is checked right here in your browser, nothing is uploaded anywhere.

Halos & fringes

Leftover background pixels along the edge glow on pure black — the classic white-outline problem.

Leftover background

Corners are sampled. If a corner isn’t fully transparent, background may still be attached.

Clipped edges

If artwork touches the canvas edge, it may be cut off. That is flagged as “Fix before listing.”

Clean exports

Download a trimmed copy or a 3-background proof sheet to eyeball before you list.

How to read the results

Once a file loads, you’ll get a plain verdict plus the numbers behind it. Three things matter most for digital downloads and print-on-demand:

On pure black, a cut-out should sit clean. The artwork itself stays fully visible — what you’re watching for is a pale outline glowing around it, which means fringe pixels from the old background are still hanging on. A little semi-transparent edge is normal anti-aliasing; a light-colored outline is the giveaway.
Corners should be fully transparent for a cut-out design. Opaque corners usually mean leftover background.
Artwork needs breathing room. If it touches any edge, leave a few transparent pixels of clearance so nothing looks clipped.

YOUR FILES

Checking…

Reading pixels.

FILE FACTS

FILE

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DIMENSIONS

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ARTWORK BOUNDS

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CLOSEST EDGE

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Transparent pixels of clearance

WHAT’S IN THE PIXELS

Opaque — Semi-transparent — Fully transparent —

CHECKS

PREVIEW ON REAL BACKGROUNDS

CheckerboardHover to inspect pixels

Pure blackWhere white halos show

Pure whiteWhere dark fringes show

Alpha maskWhite = solid, black = transparent

Derived view of your image — alpha mask or fringe highlight

EXPORT

Text report — copy it into your listing notes

A quick way to use this before listing: check the black preview first. Light, normal edge softness is fine — every anti-aliased edge has some semi-transparent pixels, and this checker does not count soft edges that match their artwork (any color, white included) as fringe. The problem is a pale, glowing outline on pure black: bright near-white pixels at the outer edge that don’t match the artwork beside them. Switch the fourth panel to Fringe highlight and only those mismatched edge pixels light up pink (normal soft edges stay dim gray), so you can see if a halo ring is really there.