Sprite Atlas Packer

Trim and pack local raster images into deterministic transparent PNG atlases.

Local browser pipeline: images are decoded and drawn in memory only. Browser decoding, color management, premultiplication, and PNG encoding can vary. Packing uses a deterministic shelf heuristic and makes no optimality claim. CSS metadata uses top-left pixel coordinates; rotated frames require consumer support.

Images and packing settings

Open images

Transparent trimming

Alpha threshold (0–255)

Padding pixels

Extrusion pixels

90° rotation

Power-of-two atlas

Square atlas

Maximum width

Maximum height

Source	Dimensions	Trim bounds	Pixels

Sprite Atlas Packer

Images and packing settings

Packing result

Exact-pixel atlas previews