Sprite-sheet packer

What it does

Pack small graphics into an atlas PNG and download a frame-coordinate JSON index.

How to use it

1. Choose 1–100 PNG, JPEG or WebP images, up to 50 MB combined and 20 MB / 40 megapixels per source.
2. Set atlas width from 32–4,096 px and padding from 0–64 px. Output height is calculated and capped at 4,096 px.
3. Images retain their pixel sizes. If a frame or total height does not fit, increase width or use fewer images. Download atlas.png and atlas.json.

Example

Three 32 × 32 sprites with 2 px padding fit across a 128 px atlas.

Methodology

A deterministic shelf layout packs images in selection order with transparent outer and inter-sprite padding. The JSON lists pixel coordinates from the top-left origin and original frame dimensions.

Limitations

No rotation, trimming, extrusion, deduplication or optimal packing. Duplicate filenames are rejected. Animation and image metadata are omitted.

Automation

This tool runs in your browser. No upload API or MCP endpoint is available.