GIMP XCF file signature
Magic number at the start of the file · gimp xcf
A GIMP image starts with the ASCII string gimp xcf followed by a space and a version tag such as v011, then the canvas dimensions and layer structure.
What this magic number means
A magic number is a short, fixed run of bytes at a known position that tells a program what a file really is, no matter what the filename says. If a file starts with the bytes 67 69 6D 70 20 78 63 66 20 (the text gimp xcf ), it is a GIMP XCF file.
Formats that use the 67 69 6D 70 signature
These file types in our database carry this signature:
How to check a file's signature
You can read the first bytes of any file yourself. The magic bytes are shown in hex, the same way this page lists them.
Linux & macOS
- xxd -l 16 example.xcf
- hexdump -C -n 16 example.xcf
- file example.xcf
Windows (PowerShell)
- Format-Hex -Path example.xcf -Count 16
Python
- open("example.xcf","rb").read(9).hex()
In your browser
- Drop the file into the WhatFileType identifier, which reads the signature without uploading it.
Frequently asked questions
What is the GIMP XCF file signature?
GIMP XCF files start with the hex bytes 67 69 6D 70 20 78 63 66 20 (gimp xcf in ASCII). This magic number identifies the format regardless of the file's name or extension.
How do I check a file's magic number?
Open the file in a hex editor, or run a command such as xxd -l 16 example.xcf on Linux or macOS, or Format-Hex -Path example.xcf -Count 16 in Windows PowerShell, and read the first bytes.
Can a file fake the GIMP XCF signature?
Renaming a file does not change its bytes, so the extension can lie but the signature usually cannot. A genuine GIMP XCF file has these exact bytes; a file with the wrong bytes is not really GIMP XCF, whatever its name says.