SpritePacker

SpritePacker is a browser-based toolkit for creating and converting sprite sheets for 2D game and web development. Combine PNG and JPG frames into compact texture atlases with MaxRects, grid, horizontal, or vertical layouts. Adjust padding, edge extrusion, transparent-border trimming, and power-of-two sizing, preview animations, then export the atlas as PNG with Phaser- and PixiJS-ready JSON, Unity-compatible XML, or CSS and SCSS. The site also includes a frame extractor, a GIF-to-sprite-sheet converter, a sprite-sheet-to-GIF converter, and engine guides for Unity, Godot, Phaser, PixiJS, and GameMaker. Decoding, packing, trimming, conversion, preview, and export all run locally in the browser with Canvas and Web Workers, so artwork is not uploaded to an application server. The tools are free, need no account, and are aimed at independent game developers, frontend developers, and pixel-art creators who want an engine-ready asset workflow without installing desktop software.