Multi-file input
Add up to 64 PNG, JPG, or WebP frames per selection.
Language: English (Canada)
Sprite sheet packer for PNG atlases
Arrange up to 64 sprite frames in a uniform-grid atlas and export matching JSON coordinates.
Free0 creditsPNG atlas + JSON
Does the sprite sheet packer upload my frames?
No. Up to 64 frames stay in the browser and are arranged in a uniform grid. You get a PNG atlas plus JSON coordinates; frames are not trimmed or rotated.
LIVE WORKSPACE
Work locally. Export cleanly.
This utility runs in your browser. Your files stay on your device and no generation credits are used.
Source & settings01
Private local processing0 credits
Add two or more frames
The utility runs locally. Your artwork is not uploaded and no credits are used.
IN THE GAME
See the assets as a game.
Explore gameplay, handheld use, and coordinated designs. These AI-generated concepts illustrate visual possibilities; review your own assets and engine imports before shipping.
One art direction across the whole game
Review the playable scene beside its characters, terrain, items, and interface as one coordinated design.
One character across directions and actions
Compare the character's proportions, colors, and action silhouettes with the world around it.
Combat, items, and interface in one scene
Judge effect visibility, item icons, and interface contrast during the same gameplay moment.
A practical example
Pack eight equal-size frames
Use a concrete input, inspect the output, and check the current limits before choosing your next step.
Example input
Download and unzip the eight demo frames below. Each transparent PNG is 32 × 32 pixels.
What to check
- Choose all eight PNG frames in sequence, then set the atlas to 4 columns.
- Inspect the preview: four 32-pixel cells across and two cells down produce a 128 × 64 atlas.
- Download the atlas PNG and JSON. Check that the first frame starts at x: 0, y: 0 and the fifth starts at x: 0, y: 32.
Expected output
Eight 32 × 32 inputs at four columns produce a 128 × 64 PNG atlas plus JSON frame coordinates.
Current limits
The local packer uses a uniform grid sized to the largest input, accepts up to 64 files, and preserves frame bounds. It does not trim, rotate, add padding, or perform optimal bin packing.
Official workflow references
Check the engine or editor documentation when preparing your own import. These sources describe file and playback behavior, not an endorsement of PixelBox.
Publisher and support
Content updated:
Published and maintained by LlamaGen. This page describes current PixelBox controls and export formats. Contact the team about incorrect information or an export problem.
01 / WHY IT WORKS
Made for production, not just previews.
Predictable layout
Choose a column count. Every cell uses the largest input width and height, and frames keep their original size.
Metadata included
Export frame names, coordinates, and dimensions as JSON.
From source to clearly labeled output.
Add frames
Select your animation or asset PNG files in sequence.
Choose columns
Set the atlas layout and inspect the generated preview.
Export both files
Download the atlas PNG and its JSON coordinates.
03 / FAQ
Clear terms before you build.
Are my frames uploaded?
No. Packing runs in your browser and the files stay on your device.
What JSON format is used?
The export contains an image name, atlas dimensions, and frame objects with x, y, width, and height. Give every frame a unique file name so each JSON entry stays distinct.
Does it trim transparent pixels?
No. The grid packer preserves original frame bounds and does not rotate frames or optimize empty space. Use the sprite sheet slicer when you need its trimming and padding controls.