{
  "id": "magic/gif",
  "family": "magic",
  "slug": "gif",
  "title": "GIF signature (GIF87a / GIF89a)",
  "summary": "A GIF file begins with a 6-byte header: the ASCII signature 'GIF' followed by a 3-byte version, either '87a' or '89a'. '89a' added transparency, animation, and application extensions.",
  "kind": "signature",
  "aliases": [
    "GIF magic",
    "GIF87a",
    "GIF89a"
  ],
  "status": "de-facto",
  "verification": "verified",
  "tier": "B",
  "source_url": "https://www.w3.org/Graphics/GIF/spec-gif89a.txt",
  "source_version": "GIF89a specification (CompuServe, 1990), Section 17 Header",
  "retrieved_date": "2026-05-29",
  "see_also": [
    "magic/png",
    "magic/jpeg"
  ],
  "ext_type": "file-signature@1",
  "ext": {
    "magic_hex": "47 49 46 38 39 61",
    "offset": 0,
    "magic_ascii": "GIF89a",
    "extensions": [
      "gif"
    ],
    "mime": "image/gif",
    "spec": "GIF89a specification (CompuServe, 1990)",
    "notes": [
      "Two versions exist: 'GIF87a' = 47 49 46 38 37 61, 'GIF89a' = 47 49 46 38 39 61.",
      "Bytes 0-2 are the signature 'GIF'; bytes 3-5 are the version '87a' or '89a'.",
      "After the 6-byte header comes the 7-byte Logical Screen Descriptor."
    ]
  },
  "updated": "2026-05-29T00:00:00Z"
}