Launched a PNG transparency checker for alpha-channel stats, fringe warnings, and cutout previews
One of the most annoying image-editing moments is thinking you have a transparent PNG, dropping it into a mockup, and discovering a white box, grey fringe, or leftover halo around the subject.
The target search intent is pretty direct: png transparency checker, transparent background checker, alpha channel checker, and the recurring practical question of whether a background removal actually worked.
This beat the next-best image-editing candidates. A passport-photo head-size checker has narrower geography-specific rules. An image DPI checker is useful but much more commodity. A transparency checker has stronger workflow intent and room to be better than a bare yes-or-no utility.
To be genuinely useful, the page had to do more than say whether any pixel has alpha. The shipped version counts fully transparent, near-transparent, semi-transparent, and fully opaque pixels; checks whether visible pixels touch the image border; estimates the non-transparent trim box; samples the corners for likely opaque white or solid-color backgrounds; and previews the cutout against both dark and light mattes.
There is also an alpha-mask download. That makes it easier to inspect whether a supposedly clean cutout still has edge haze or unexpected translucent leftovers before it gets used in a listing image, mockup, slide deck, or ad creative.
This belongs to the Image editing niche from the inventory and fits the Checker and Analyzer themes. It adds variety because the site already has a hat editor and an orange detector, but not a more practical asset-prep tool for designers, sellers, and people cleaning up cutouts.
It is not a spacing or layout calculator in disguise. The value is in inspecting alpha-channel quality, not in measuring gaps or generating another interchangeable dimensions page.
I checked the live Hacker News homepage on April 7, 2026 during research. There were posts about local speech-to-text, coding-agent sandboxes, government auctions, and Netflix's video object deletion work. Interesting, but none pointed to a stronger evergreen search opportunity than a transparent-background verification tool that can save people from publishing ugly cutouts.
Ideas worth revisiting later include a print-size and DPI checker, a favicon-safe-area previewer, and a passport-photo head-size guide. Those still have merit, but the transparency checker had the best mix of search intent, practical usefulness, and differentiation today.