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IFB (.ifb)

.ifb file signature | text/calendar

IFB is a text-based calendar format associated with the iCalendar standard, maintained by the Internet Engineering Task Force (IETF) through its RFC specifications. It is used for exchanging calendar data such as events, schedules, reminders, and availability information in applications including email clients, personal information managers, and groupware systems. The format is generally safe, although calendar files may include links, attachments, or alarms that should be reviewed when received from untrusted sources.

Safe

Magic Bytes

Offset 0
42 45 47 49 4E 3A 56 43 41 4C 45 4E 44 41 52

Sources: Apache Tika

Extension

.ifb

MIME Type

text/calendar

Byte Offset

0

Risk Level

Safe

Validation Code

How to validate .ifb files in Python

Python 
def is_ifb(file_path: str) -> bool:
    """Check if file is a valid IFB by magic bytes."""
    signature = bytes([0x42, 0x45, 0x47, 0x49, 0x4E, 0x3A, 0x56, 0x43, 0x41, 0x4C, 0x45, 0x4E, 0x44, 0x41, 0x52])
    with open(file_path, "rb") as f:
        return f.read(15) == signature

How to validate .ifb files in Node.js

Node.js 
function isIFB(buffer: Buffer): boolean {
  const signature = Buffer.from([0x42, 0x45, 0x47, 0x49, 0x4E, 0x3A, 0x56, 0x43, 0x41, 0x4C, 0x45, 0x4E, 0x44, 0x41, 0x52]);
  return buffer.subarray(0, 15).equals(signature);
}

How to validate .ifb files in Go

Go 
func IsIFB(data []byte) bool {
    signature := []byte{0x42, 0x45, 0x47, 0x49, 0x4E, 0x3A, 0x56, 0x43, 0x41, 0x4C, 0x45, 0x4E, 0x44, 0x41, 0x52}
    if len(data) < 15 {
        return false
    }
    return bytes.Equal(data[:15], signature)
}

API Endpoint

GET /api/v1/ifb
curl https://filesignature.org/api/v1/ifb

See the full API documentation for all endpoints and parameters.

Related Formats

.ics .vcf .vcs

Frequently Asked Questions

What is a .ifb file?

A .ifb file is identified by the magic bytes 42 45 47 49 4E 3A 56 43 41 4C 45 4E 44 41 52 at byte offset 0. IFB is a text-based calendar format associated with the iCalendar standard, maintained by the Internet Engineering Task Force (IETF) through its RFC specifications. It is used for exchanging calendar data such as events, schedules, reminders, and availability information in applications including email clients, personal information managers, and groupware systems. The format is generally safe, although calendar files may include links, attachments, or alarms that should be reviewed when received from untrusted sources.

What are the magic bytes for .ifb files?

The magic bytes for IFB files are 42 45 47 49 4E 3A 56 43 41 4C 45 4E 44 41 52 at byte offset 0. These bytes uniquely identify the file format regardless of the file extension.

How do I validate a .ifb file?

To validate a .ifb file, read the first bytes of the file and compare them against the known magic bytes (42 45 47 49 4E 3A 56 43 41 4C 45 4E 44 41 52) at offset 0. This is more reliable than checking the file extension alone, as extensions can be renamed.

What is the MIME type for .ifb files?

The primary MIME type for .ifb files is text/calendar.

Is it safe to open .ifb files?

IFB (.ifb) 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.