What is a .sketch file?
Sketch Design Document · Design · Sketch B.V. · 2010
A .sketch file is a design document from Sketch, the macOS interface-design tool. Modern Sketch files are ZIP packages of JSON describing the artboards, layers and styles of a UI design.
What is a .sketch file used for?
Since a .sketch is a ZIP of JSON, it starts with the ZIP signature and can be unzipped to inspect its structure. Sketch is Mac-only, which is the usual sticking point for people on other systems.
To view a Sketch file without the app, use the free Sketch web viewer, or open it in tools like Figma (import) or Lunacy on Windows, which read the format.
How to open a .sketch file
The .sketch format opens in the following apps, grouped by operating system. If one app does not work, try another from the same list. For a step-by-step walkthrough, see how to open a .sketch file.
Windows
- Lunacy
- Figma (import)
- 7-Zip (to inspect)
macOS
- Sketch
- Lunacy
- Figma (import)
Linux
- Lunacy
- Figma (web)
Web
- Sketch web viewer
- Figma
How to convert a .sketch file
You can convert a .sketch file to fig, pdf, png, svg using a conversion tool or the export menu of an app that opens it.
.sketch file signature (magic bytes)
Programs recognise a .sketch file by the bytes at the start of the file, not by its name. These are the signatures for Sketch. For a full breakdown, see the Sketch file signature page.
| Hex signature | Offset | Note |
|---|---|---|
| 50 4B 03 04 | 0 | ZIP package (PK..) |
See the full magic-numbers reference for every format.
Frequently asked questions
What is a .sketch file?
A .sketch file is a design document from Sketch, the macOS interface-design tool. Modern Sketch files are ZIP packages of JSON describing the artboards, layers and styles of a UI design.
How do I open a .sketch file on Windows?
Use Lunacy, a free Windows app that opens Sketch files, or import it into Figma. To just peek inside, rename it to .zip.
Is a .sketch file a ZIP?
Modern Sketch files are, yes: a ZIP of JSON and images. That is why they start with the ZIP signature and can be unzipped.
Can Figma open Sketch files?
Yes. Figma can import .sketch files, converting the artboards and layers, which is a common way to open them off a Mac.
Related formats
Sources
Details on this page were checked against authoritative references: