diff --git a/internal/magic/image.go b/internal/magic/image.go
index 9766ca2c..1102b06f 100644
--- a/internal/magic/image.go
+++ b/internal/magic/image.go
@@ -42,6 +42,14 @@ var (
 	Xpm = prefix([]byte{0x2F, 0x2A, 0x20, 0x58, 0x50, 0x4D, 0x20, 0x2A, 0x2F})
 )
 
+func Avif(raw []byte, limit uint32) bool {
+	if len(raw) < 24 {
+		return false
+	}
+	return bytes.Equal(raw[4:8], []byte("ftyp")) &&
+		bytes.Equal(raw[20:24], []byte("avif"))
+}
+
 func jpeg2k(sig []byte) Detector {
 	return func(raw []byte, _ uint32) bool {
 		if len(raw) < 24 {
diff --git a/mimetype_test.go b/mimetype_test.go
index d123eabd..b516a5d7 100644
--- a/mimetype_test.go
+++ b/mimetype_test.go
@@ -33,6 +33,7 @@ var files = map[string]string{
 	"atom.atom":          "application/atom+xml",
 	"au.au":              "audio/basic",
 	"avi.avi":            "video/x-msvideo",
+	"avif.avif":          "image/avif",
 	"bmp.bmp":            "image/bmp",
 	"bpg.bpg":            "image/bpg",
 	"bz2.bz2":            "application/x-bzip2",
diff --git a/testdata/avif.avif b/testdata/avif.avif
new file mode 100644
index 00000000..9d869c5b
Binary files /dev/null and b/testdata/avif.avif differ
diff --git a/tree.go b/tree.go
index 757ffed9..a1e2dccd 100644
--- a/tree.go
+++ b/tree.go
@@ -20,7 +20,7 @@ var root = newMIME("application/octet-stream", "",
 	midi, ape, musePack, amr, wav, aiff, au, mpeg, quickTime, mqv, mp4, webM,
 	threeGP, threeG2, avi, flv, mkv, asf, aac, voc, aMp4, m4a, m3u, m4v, rmvb,
 	gzip, class, swf, crx, ttf, woff, woff2, otf, eot, wasm, shx, dbf, dcm, rar,
-	djvu, mobi, lit, bpg, sqlite3, dwg, nes, lnk, macho, qcp, icns, heic,
+	djvu, mobi, lit, bpg, sqlite3, dwg, nes, lnk, macho, qcp, icns, avif, heic,
 	heicSeq, heif, heifSeq, hdr, mrc, mdb, accdb, zstd, cab, rpm, xz, lzip,
 	torrent, cpio, tzif, xcf, pat, gbr, glb,
 	// Keep text last because it is the slowest check
@@ -115,6 +115,7 @@ var (
 	icns = newMIME("image/x-icns", ".icns", magic.Icns)
 	psd  = newMIME("image/vnd.adobe.photoshop", ".psd", magic.Psd).
 		alias("image/x-psd", "application/photoshop")
+	avif    = newMIME("image/avif", ".avif", magic.Avif)
 	heic    = newMIME("image/heic", ".heic", magic.Heic)
 	heicSeq = newMIME("image/heic-sequence", ".heic", magic.HeicSequence)
 	heif    = newMIME("image/heif", ".heif", magic.Heif)