asat

.asatAseprite Sprite Sheet

David Reid (Aseprite) · 2014

Developer
David Reid (Aseprite)
Category
Images
MIME Type
application/octet-stream
First Released
2014
Open Format
No
File Signature
Not easily identifiable as a standard magic byte sequence for universal recognition.
At a Glance
.asat
Aseprite Sprite Sheet

.asat is the native project file format for Aseprite, used for creating and managing pixel art sprites and animations.

Reviewed on July 5, 2026
Compression
Binary / Varies
Transparency
Yes
Editability
High
Best for
Pixel art animation projects

Key Features

  • Preserves layers, frames, and color palettes.
  • Includes full undo history for seamless editing.
  • Supports advanced animation features like onion skinning.
  • Optimized for pixel art and sprite sheet creation.

Best For

  • Saving ongoing pixel art animation projects.
  • Storing complex sprite sheets with multiple frames.
  • Maintaining editable layers and palettes for pixel art.
  • Collaborating on pixel art projects within Aseprite.

Less Ideal For

  • Distributing final, ready-to-display images or animations.
  • Web embedding where a universally supported format is needed.
  • Sharing simple static images that don't require editing.
  • Archiving large collections of individual frames without animation context.

Common Use Cases

  • Creating sprite sheets for video games.
  • Designing animated characters and objects for indie games.
  • Developing animated GIFs and short looping animations.
  • Prototyping UI elements with animation.

How to Open It

  1. Open the .asat file directly within Aseprite.
  2. Ensure you have Aseprite installed on your operating system (Windows, macOS, Linux).
  3. If you only have the exported image, you will not be able to edit it as an .asat file.

What is a .asat file?

The .asat file format is the native file format for Aseprite, a popular pixel art and animation editor. It's designed specifically for creating and managing sprite sheets, allowing artists to store multiple frames of animation or individual sprites within a single file. This format preserves all the editing information, including layers, frames, color palettes, and undo history, making it ideal for iterative design and complex animation projects. Unlike static image formats, .asat files act as a comprehensive project file, ensuring that all your creative assets and editing states are saved and accessible.

Programs That Open .asat Files

PlatformProgram
WindowsAsepritePaidOfficial
macOSAsepritePaidOfficial
LinuxAsepritePaidOfficial

How to Convert .asat Files

FormatMethod
.PNGAseprite Export, ImageMagick
.GIFAseprite Export

Common Problems with .asat Files

⚠️ Cannot open .asat file.
Ensure you have Aseprite installed, as it is the primary software for this format. .asat files are project files, not standard image formats.
⚠️ Exported animation looks choppy.
Check the frame rate and duration settings within Aseprite before exporting. Ensure all frames are correctly sequenced and have appropriate timing.

Frequently Asked Questions

Can I open .asat files in Photoshop?

No, .asat is a proprietary format for Aseprite and cannot be directly opened or edited in software like Adobe Photoshop.

What's the difference between .ase and .asat?

The .ase (Aseprite) format is an older version or an alternative save format for Aseprite, while .asat is the current, more feature-rich native project format.

Is .asat a compressed image format?

No, .asat is a project file container that stores all editing data, including pixel information, layers, and animation frames, rather than being a final compressed image format.

Technical Details

Aseprite's .asat files are binary files that contain all project data. This includes pixel data for each frame, layer information, palette data, and metadata like undo history. The format is structured to efficiently store and retrieve animation frames, making it suitable for real-time game development and animation workflows. It's not a compressed image format in the typical sense but rather a project container.

Did You Know?

Aseprite is written in C++ using the Skia graphics library.
The .asat format evolved from the earlier .ase format to better support Aseprite's growing feature set.

Security Information

.asat files are generally safe as they are project files for a trusted application. However, as with any executable or project file, exercise caution if downloading from untrusted sources, though this format is primarily for image editing projects.

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