---
type: lookup
id: ilbm-lbm-ibm-iff-46-4f-52-4d-49-4c-42-4d
asset: file-format-signatures
title: "46 4F 52 4D ?? ?? ?? ?? 49 4C 42 4D — File format magic numbers"
sources:
  - https://en.wikipedia.org/wiki/List_of_file_signatures
source_quote: "<https://en.wikipedia.org/wiki/Interchange_File_Format> IFF <https://en.wikipedia.org/wiki/ILBM> Interleaved Bitmap Image"
generated: true
verified: false
harvested: 2026-08-03
stale_after: 2027-08-03
hex_signature: "46 4F 52 4D ?? ?? ?? ?? 49 4C 42 4D"
offset: "0 any"
extension: "ilbm lbm ibm iff"
format: "IFF ILBM Interleaved Bitmap Image"
unverified_fields: extension, format, hex_signature, offset
---
**Hex signature:** 46 4F 52 4D ?? ?? ?? ?? 49 4C 42 4D

**Offset:** 0 any

**Extension:** ilbm lbm ibm iff

**Format:** IFF ILBM Interleaved Bitmap Image

> <https://en.wikipedia.org/wiki/Interchange_File_Format> IFF <https://en.wikipedia.org/wiki/ILBM> Interleaved Bitmap Image

Source: <https://en.wikipedia.org/wiki/List_of_file_signatures>