Turn an .ase or .aseprite animation into a packed spritesheet in your browser, with padding and extrusion for engine importers. No account needed.
Open BitRasterFree, runs in the browser, no account needed.
The sheet is written alongside sidecar JSON in the layout Aseprite produces, which is what Unity and most engine importers already read - so this is a drop-in replacement for an Aseprite export step in a pipeline.