FT11 (.ft11)

.ft11 file signature | image/x-freehand

Safe

Magic Bytes

Offset 0


              41 47 44 32

Sources: Apache Tika

All Known Signatures

6 signature variants are documented for .ft11 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

.ft11

MIME Type

image/x-freehand

Byte Offset

Risk Level

Safe

Validation Code

How to validate .ft11 files in Python

Python

def is_ft11(file_path: str) -> bool:
    """Check if file is a valid FT11 by magic bytes."""
    signature = bytes([0x41, 0x47, 0x44, 0x32])
    with open(file_path, "rb") as f:
        return f.read(4) == signature

How to validate .ft11 files in Node.js

Node.js

function isFT11(buffer: Buffer): boolean {
  const signature = Buffer.from([0x41, 0x47, 0x44, 0x32]);
  return buffer.subarray(0, 4).equals(signature);
}

How to validate .ft11 files in Go

func IsFT11(data []byte) bool {
    signature := []byte{0x41, 0x47, 0x44, 0x32}
    if len(data) < 4 {
        return false
    }
    return bytes.Equal(data[:4], signature)
}

API Endpoint

GET /api/v1/ft11


              curl https://filesignature.org/api/v1/ft11

See the full API documentation for all endpoints and parameters.

Frequently Asked Questions

What is a .ft11 file?

A .ft11 file is a FT11 file.

What are the magic bytes for .ft11 files?

The magic bytes for FT11 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 .ft11 file?

To validate a .ft11 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 .ft11 files?

The primary MIME type for .ft11 files is image/x-freehand.

Is it safe to open .ft11 files?

FT11 (.ft11) 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.