Color Key Background Remover

• Choose Source image, then set Background key color as #RRGGBB.
• Set whole-number Tolerance and Feather from 0 to 442. Keep Edge-connected pixels only selected for four-neighbor boundary paths, or clear it to process all pixels.
• Select Remove keyed background. Select Download result for cutout.png and Download color-key-report.json for counts. Cancel discards unfinished output; Reset restores the defaults.

A black edge around a white ring is removed while an enclosed black center remains in edge mode. Global mode also removes that center.

• One static PNG, JPEG or WebP up to 20 MiB, 12 million decoded pixels and 16,384 pixels per side; 20 MiB PNG, 64 KiB report and 60-second operation limit.
• Color distance is Euclidean encoded 8-bit RGB, with no subject detection, spill correction or semantic segmentation. A feather ramp changes alpha; fully transparent output RGB is canonical zero.
• Four-neighbor edge paths include already-transparent pixels. With feather zero, matching distance is at most tolerance; otherwise traversal stops at the outer feather boundary.
• Native decoding applies source orientation once and may round partially transparent colors. Alpha-change counts distinguish fully cleared, partly cleared and unchanged alpha, including already-transparent pixels.
• Explicit pixel/visited/queue buffers use at most 108 MB; native browser bitmap/canvas and input allocations are additional. New work may wait for cancelled native processing to drain.
• Output is newly encoded and source EXIF/text metadata is not copied. Pixels and allowed color/density metadata are not an anonymity guarantee.