Pyxel Edit Alternative
Pyxel Edit stalled. Your tilesets don't have to.
Pyxel Edit is still sold as a beta, but its own site warns there is no guarantee it will ever be finished, and updates stopped years ago. Novaboard opens your .pyxel files in the browser, free, with layers, frames, and a seamless tile preview while you paint.

Import your .pyxel files
Drop a .pyxel file into Novaboard and your layers and frames come with it. When a project is done, export onward to PNG, GIF, sprite sheets with JSON metadata, or even .aseprite.

Tile mode: see seams while you paint
Turn on tile mode and the canvas repeats live in every direction, so seams show up while you paint, not after you export. Tile instancing and tilemaps, the part Pyxel Edit was known for, are on the roadmap; drawing and animating the tiles themselves works today.
Animation is not an afterthought
A full timeline with onion skinning, tweening, and animation tags sits next to your tiles. Animate props, characters, and effects in the same workspace as the tiles they belong to.

Free in the browser, no beta purchase
Pyxel Edit charges for software that may never be finished. Novaboard is free in your browser with no account, your files stay on your device, and updates ship regularly.