- dimensions
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- pixels
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- average opacity
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- opaque
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- semi-transparent
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- fully transparent
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Drop a PNG / WebP here
or click to choose · or paste (Ctrl/Cmd + V)
processed in your browser · never uploaded
This is an alpha (transparency) viewer for confirming that a cutout or generated image is actually transparent — and that no background fill or semi-transparent fringe is left behind. Load a PNG or WebP and it's drawn over a checkerboard pattern, so transparent areas show the checker through them while opaque areas show the image. At the same time the original alpha channel is scanned pixel by pixel to report how many pixels (and what share) are opaque, semi-transparent, or fully transparent, along with the average opacity. The background can be switched between checker, white, black, and magenta (a classic color for spotting leftover backgrounds): a white background makes dark edges obvious, a black one reveals bright fringes. Turn on "highlight semi-transparent" and every pixel whose alpha is neither fully opaque nor fully transparent is painted red, so you can pinpoint a halo around a cutout edge or a faint area you missed erasing. A zoom slider scales the image to actual pixels and beyond with crisp pixel rendering, so you can inspect edges closely. It also clears up the opposite mistake — an image you thought was transparent turning out to be fully opaque. Your assets are your work, so this tool uploads nothing — loading, checking, and rendering all happen locally in your browser.
How to use
- Drop the PNG / WebP you want to check (or click to choose, or paste with Ctrl/Cmd+V).
- Switch the background between checker, white, black and magenta to watch where it shows through, and adjust checker size or zoom as needed.
- Turn on "highlight semi-transparent" to mark any leftover edge alpha (halo) in red, and read the breakdown of opaque / semi-transparent / fully transparent pixels.
FAQ
Are my images uploaded to a server?
No. Loading the image, checking its alpha, and drawing it on the checkerboard all happen in your browser. Nothing is uploaded, stored, or sent anywhere — everything is processed only on your device.
What's the difference between "semi-transparent" and "fully transparent"?
A pixel with alpha 0 (completely see-through, so the checker shows) is counted as fully transparent, alpha 255 (completely solid) as opaque, and anything in between (1–254) as semi-transparent. The blur left on a cutout edge is mostly semi-transparent, which is exactly what the highlight reveals.
Why is there a magenta background?
Magenta (vivid pink) almost never appears in natural images, so any leftover background or a soft semi-transparent edge stands out against it and is hard to miss. Combine it with the white and black backgrounds to catch both dark edges and bright fringes.
It says there's no transparency — what does that mean?
It means every pixel's alpha is 255 (opaque). Formats that can't store transparency (like JPEG), or a PNG whose transparent areas were filled with white, show up this way. Nothing shows through the checkerboard, so the image has no transparent areas.
Can I download a file?
This tool is a viewer focused on checking transparency, so it has no save/export step. It doesn't erase transparency or bake in the checker — it simply loads your original image and displays it.
Which formats are supported?
Any image your browser can display (PNG, WebP, GIF, AVIF, and more). Since the point is checking transparency, it's most useful with formats that can carry an alpha channel — PNG, WebP, and AVIF.