FH (.fh)
.fh file signature | image/x-freehand
Magic Bytes
Offset 0
41 47 44 32
Sources: Apache Tika
All Known Signatures
6 signature variants are documented for .fh files across multiple sources.
| Hex Signature | Offset | Sources |
|---|---|---|
| 41 47 44 32 | 0 | Apache Tika |
| 41 47 44 33 | 0 | Apache Tika |
| 41 47 44 34 | 0 | Apache Tika |
| 46 72 65 65 48 61 6E 64 31 30 | 0 | Apache Tika |
| 46 72 65 65 48 61 6E 64 31 31 | 0 | Apache Tika |
| 46 72 65 65 48 61 6E 64 31 32 | 0 | Apache Tika |
Extension
.fh
MIME Type
image/x-freehand
Byte Offset
0
Risk Level
Safe
Validation Code
How to validate .fh files in Python
def is_fh(file_path: str) -> bool:
"""Check if file is a valid FH by magic bytes."""
signature = bytes([0x41, 0x47, 0x44, 0x32])
with open(file_path, "rb") as f:
return f.read(4) == signatureHow to validate .fh files in Node.js
function isFH(buffer: Buffer): boolean {
const signature = Buffer.from([0x41, 0x47, 0x44, 0x32]);
return buffer.subarray(0, 4).equals(signature);
}How to validate .fh files in Go
func IsFH(data []byte) bool {
signature := []byte{0x41, 0x47, 0x44, 0x32}
if len(data) < 4 {
return false
}
return bytes.Equal(data[:4], signature)
}API Endpoint
/api/v1/fh
curl https://filesignature.org/api/v1/fh
See the full API documentation for all endpoints and parameters.
Frequently Asked Questions
What is a .fh file?
A .fh file is a FH file.
What are the magic bytes for .fh files?
The magic bytes for FH files are 41 47 44 32 at byte offset 0. These bytes uniquely identify the file format regardless of the file extension.
How do I validate a .fh file?
To validate a .fh file, read the first bytes of the file and compare them against the known magic bytes (41 47 44 32) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.
What is the MIME type for .fh files?
The primary MIME type for .fh files is image/x-freehand.
Is it safe to open .fh files?
FH (.fh) files are generally safe to open. They are classified as low risk because they primarily contain data rather than executable code. However, always ensure files come from a trusted source.