What is a magic number / file signature?

A magic number is a constant sequence of bytes (usually at offset 0 of a file, sometimes at a fixed offset like 0x8001 for ISO9660) that uniquely identifies a file format. For example, every PNG file starts with the 8 bytes 89 50 4E 47 0D 0A 1A 0A, every PDF starts with %PDF, and every ZIP-based file starts with PK\x03\x04. The operating system, browsers, and forensic tools use these signatures instead of the (user-editable) file extension to decide what a file really is.

How does the inspector detect file type?

Drop or pick a file (or paste hex bytes) and the tool reads the first/last few KB locally via FileReader/Blob.slice, then runs a pure-JS matching engine over a 100+ entry signature database. Each rule specifies a byte pattern, an offset (usually 0, but 0x8001 for ISO9660, 4 for MP4 ftyp atoms, 257 for TAR ustar, etc.), an optional trailer, and an optional mask. Multiple matching rules are listed with confidence; ZIP-based files are further disambiguated by peeking at the central directory (docx / xlsx / pptx / jar / apk / epub / odt).

What is extension spoofing and how is it flagged?

Extension spoofing is when a file's extension doesn't match its true type — e.g. a PNG renamed to .jpg, or a Windows executable renamed to .pdf to evade mail filters. The tool compares the extension of the dropped file against the extension(s) implied by the detected signature(s) and shows a prominent warning when they disagree. The verdict banner displays MATCH (extension matches signature), SPOOF (extension contradicts signature), or UNKNOWN (no signature matched — common for plain text, CSV, JSON, log files).

Can I search the signature database without a file?

Yes. The reference table is searchable by extension (e.g. 'png'), MIME type (e.g. 'application/pdf'), format name (e.g. 'ELF'), or hex bytes (e.g. '89504E47' or '89 50 4E 47'). Each entry shows the signature bytes, offset, trailer (if any), MIME type, typical extensions, category, and a short description. The database is bundled in the JS bundle — no network needed.

What extra features does this tool have compared to other magic-number checkers?

(1) 100+ format database covering images, archives, executables, documents, audio, video, fonts, databases, ROMs, and more. (2) Offset-aware matching (ISO9660 at 0x8001, TAR ustar at 257, MP4 ftyp at 4, etc.). (3) Trailer checks (WAV/AVI/WebP after RIFF, DMG koly at EOF, etc.). (4) ZIP-based container disambiguation (docx/xlsx/pptx/jar/apk/epub/odt/ods/odp). (5) Extension-spoof warnings. (6) Mini hex dump of the first 64 bytes with matched bytes highlighted. (7) Multiple-candidate listing with confidence. (8) Searchable reference table by ext / MIME / name / hex. (9) Hex-byte input fallback (paste 'FFD8FFE0' instead of dropping a file). (10) Plain-text / no-magic detection with a friendly 'no signature' verdict. (11) History (localStorage, last 20). (12) Shareable URL with the hex input round-tripped (for small inputs). 100% client-side and offline — your bytes never leave the device.

Developer Runs in your browser

Binary File Signature & Magic Number Inspector

Detect a file's true type from its leading magic bytes (and trailer where relevant) using a 100+ entry bundled signature database (PNG, JPG, GIF, PDF, ZIP, ELF, PE, Mach-O, OLE, SQLite, WASM, GLB, ISO9660, and more). Show a hex dump of the header bytes with matched bytes highlighted, resolve ZIP-based container subtypes (docx / xlsx / pptx / jar / apk / epub / odt), explicitly warn on extension spoofing, and search the database by extension / MIME / format name / hex signature. 100% client-side, nothing uploaded.

100% Private Works Offline Instant

Drop a file (or paste hex bytes)

Drag & drop a binary file, or paste hex bytes (e.g. 89504E47 or 89 50 4E 47) or text. Files are read locally with FileReader — never uploaded.

MATCH

Detected: PNG image

Primary match

Format

PNG image

MIME

image/png

Extension(s)

png

Hex dump (first 512 bytes; matched bytes highlighted)

00000000  89 50 4E 47 0D 0A 1A 0A 00 00 00 0D 49 48 44 52  |.PNG........IHDR|

Actions

Signature database (131 entries)

Showing 131 of 131 entries

Name	Ext	MIME	Hex magic	Off	Cat
PNG imagematched Portable Network Graphics; 8-byte signature includes newline defense against binary corruption.	png	image/png	89 50 4E 47 0D 0A 1A 0A	0x0	Image
JPEG image JPEG/JFIF image; SOI marker followed by an APPn marker (FF E0 / FF E1 …).	jpg, jpeg	image/jpeg	FF D8 FF	0x0	Image
GIF image (87a) Graphics Interchange Format, original 1987 version.	gif	image/gif	47 49 46 38 37 61	0x0	Image
GIF image (89a) Graphics Interchange Format, 1989 version (adds animation and transparency).	gif	image/gif	47 49 46 38 39 61	0x0	Image
BMP image Windows bitmap; 'BM' magic followed by file size and reserved fields.	bmp, dib	image/bmp	42 4D	0x0	Image
TIFF image (little-endian) Tagged Image File Format, little-endian byte order ('II' + 42).	tif, tiff	image/tiff	49 49 2A 00	0x0	Image
TIFF image (big-endian) Tagged Image File Format, big-endian byte order ('MM' + 42).	tif, tiff	image/tiff	4D 4D 00 2A	0x0	Image
WebP image RIFF container with 'WEBP' four-cc at offset 8.	webp	image/webp	52 49 46 46	0x0	Image
HEIF image (HEIC) High-Efficiency Image Container (Apple); 'ftypheic' at offset 4.	heic, heif	image/heic	66 74 79 70 68 65 69 63	0x4	Image
AVIF image AV1 Image File Format; 'ftypavif' at offset 4.	avif	image/avif	66 74 79 70 61 76 69 66	0x4	Image
Windows icon (ICO) Windows ICO resource; reserved 2 zero bytes then 01 00.	ico	image/x-icon	00 00 01 00	0x0	Image
Windows cursor (CUR) Windows CUR cursor; reserved 2 zero bytes then 02 00.	cur	application/x-cursor	00 00 02 00	0x0	Image
Photoshop document Adobe Photoshop document; '8BPS'.	psd	image/vnd.adobe.photoshop	38 42 50 53	0x0	Image
IFF/ILBM image (Amiga) Interchangeable File Format; 'FORM' container.	iff, ilbm	image/x-ilbm	46 4F 52 4D	0x0	Image
PCX image PC Paintbrush; version byte 0x0A followed by encoding 0x05.	pcx	image/x-pcx	0A 05	0x0	Image
Truevision TGA (v2) TGA v2 footer 'TRUEVISION-XFILE' (often at end of file).	tga	image/x-tga	54 52 55 45 56 49 53 49 4F 4E 2D 58 46 49 4C 45	0x0	Image
ZIP archive PKZIP local file header; 'PK\x03\x04'.	zip	application/zip	50 4B 03 04	0x0	Archive
Empty ZIP archive PKZIP end-of-central-directory; empty archive.	zip	application/zip	50 4B 05 06	0x0	Archive
Spanned ZIP archive PKZIP spanned-archive marker; 'PK\x07\x08'.	zip	application/zip	50 4B 07 08	0x0	Archive
RAR archive (v4) RAR v4 signature; 'Rar!\x1A\x07\x00'.	rar	application/x-rar-compressed	52 61 72 21 1A 07 00	0x0	Archive
RAR archive (v5) RAR v5 signature; 'Rar!\x1A\x07\x01\x00'.	rar	application/x-rar-compressed	52 61 72 21 1A 07 01 00	0x0	Archive
GZIP archive GZIP magic; \x1F\x8B.	gz, gzip	application/gzip	1F 8B	0x0	Archive
7-Zip archive 7-Zip signature; '7z\xBC\xAF\x27\x1C'.	7z	application/x-7z-compressed	37 7A BC AF 27 1C	0x0	Archive
BZIP2 archive Bzip2 magic; 'BZh' + level digit.	bz2, bzip2	application/x-bzip2	42 5A 68	0x0	Archive
XZ archive XZ Utils signature; '\xFD7zXZ\x00'.	xz	application/x-xz	FD 37 7A 58 5A 00	0x0	Archive
LZ4 archive LZ4 frame magic; '\x04\x22M\x18'.	lz4	application/x-lz4	04 22 4D 18	0x0	Archive
Zstandard archive Zstandard frame magic; '\x28\xB5/\xFD'.	zst, zstd	application/zstd	28 B5 2F FD	0x0	Archive
Microsoft Cabinet MSCF cabinet file; 'MSCF'.	cab	application/vnd.ms-cab-compressed	4D 53 43 46	0x0	Archive
TAR archive (USTAR) POSIX/USTAR tape archive; 'ustar' magic at byte offset 257.	tar	application/x-tar	75 73 74 61 72	0x101	Archive
CPIO archive (newc) cpio new ASCII format; '070701'.	cpio	application/x-cpio	30 37 30 37 30 31	0x0	Archive
CPIO archive (odc) cpio old ASCII format; '070707'.	cpio	application/x-cpio	30 37 30 37 30 37	0x0	Archive
ISO 9660 disc image ISO 9660 volume descriptor; 'CD001' at offset 32769 (0x8001).	iso	application/x-iso9660-image	43 44 30 30 31	0x8001	Archive
Apple Disk Image (DMG) DMG UDIF trailer 'koly' at end-of-file; the leading bytes are usually zlib-compressed.	dmg	application/x-apple-diskimage	78 01 73 DA 62 70 6F 6F	0x0	Archive
Unix ar archive Unix ar archive; '!<arch>\n' (used by .a static libraries and .deb packages).	a, ar	application/x-archive	21 3C 61 72 63 68 3E 0A	0x0	Archive
ALZip archive ALZip archive; 'ALZ\x01'.	alz	application/x-alz-compressed	41 4C 5A 01	0x0	Archive
StuffIt archive StuffIt classic; 'SIT!'.	sit	application/x-stuffit	53 49 54 21	0x0	Archive
LHA archive LHArc archive; '-lh' at offset 2.	lha, lzh	application/x-lzh-compressed	2D 6C 68	0x2	Archive
ACE archive ACE archive; 'ACE' at offset 7.	ace	application/x-ace-compressed	2A 41 43 45 2A	0x7	Archive
ARC archive SEA ARC archive; \x1A + method byte.	arc	application/x-arc	1A 08	0x0	Archive
ELF executable Executable and Linkable Format; '\x7FELF'. Used by Linux, BSD, Solaris binaries and .so shared objects.	elf, so, bin	application/x-elf	7F 45 4C 46	0x0	Executable
DOS / Windows PE executable PE/COFF or MZ DOS executable; 'MZ' (initials of Mark Zbikowski).	exe, dll	application/x-msdownload	4D 5A	0x0	Executable
Mach-O 32-bit (LE) Mach-O 32-bit little-endian; used by macOS/iOS.	macho, dylib	application/x-mach-binary	FE ED FA CE	0x0	Executable
Mach-O 64-bit (LE) Mach-O 64-bit little-endian; current macOS default.	macho, dylib	application/x-mach-binary	FE ED FA FE	0x0	Executable
Mach-O 32-bit (BE) Mach-O 32-bit big-endian (PowerPC).	macho	application/x-mach-binary	CE FA ED FE	0x0	Executable
Mach-O 64-bit (BE) Mach-O 64-bit big-endian (PowerPC 64).	macho	application/x-mach-binary	CF FA ED FE	0x0	Executable
Mach-O Universal (fat) Mach-O Universal binary; multi-architecture wrapper.	macho, dylib	application/x-mach-binary	CA FE BA BE	0x0	Executable
Java class file JVM bytecode; 'CAFEBABE' (also used by Mach-O fat binaries — context disambiguates).	class	application/java-vm	CA FE BA BE	0x0	Executable
WebAssembly module WebAssembly magic; '\x00asm'.	wasm	application/wasm	00 61 73 6D	0x0	Executable
LE/NE linear executable OS/2 LE / Windows NE linear executable — also MZ-prefixed.	exe, dll	application/x-msdownload	4D 5A	0x0	Executable
WAVE audio RIFF container with 'WAVE' four-cc at offset 8.	wav	audio/wav	52 49 46 46	0x0	Audio
Ogg media Ogg transport layer; 'OggS'.	ogg, oga, ogv	application/ogg	4F 67 67 53	0x0	Audio
FLAC audio Free Lossless Audio Codec; 'fLaC'.	flac	audio/flac	66 4C 61 43	0x0	Audio
MP3 audio (ID3) MP3 with ID3v2 tag; 'ID3' followed by version + flags.	mp3	audio/mpeg	49 44 33	0x0	Audio
MP3 audio (frame sync) MP3 frame sync (11 bits set); FF FB / FF F3 / FF F2 / FF E3 etc.	mp3	audio/mpeg	FF FB	0x0	Audio
AAC audio (ADTS) Advanced Audio Coding ADTS frame; FF F1 (also FF F9).	aac	audio/aac	FF F1	0x0	Audio
MIDI audio Standard MIDI File; 'MThd'.	mid, midi	audio/midi	4D 54 68 64	0x0	Audio
AMR audio Adaptive Multi-Rate audio; '#!AMR'.	amr	audio/amr	23 21 41 4D 52	0x0	Audio
Sun/NeXT AU audio Sun/NeXT audio; '.snd'.	au, snd	audio/basic	2E 73 6E 64	0x0	Audio
AIFF audio Audio Interchange File Format; 'FORM' + 'AIFF'.	aif, aiff	audio/aiff	46 4F 52 4D	0x0	Audio
AVI video RIFF container with 'AVI ' four-cc at offset 8.	avi	video/x-msvideo	52 49 46 46	0x0	Video
MP4 video ISO base media file format; 'ftyp' atom at offset 4.	mp4, m4v	video/mp4	66 74 79 70	0x4	Video
QuickTime movie QuickTime container; 'moov' or 'mdat' atom at offset 4.	mov, qt	video/quicktime	6D 6F 6F 76	0x4	Video
Matroska / WebM EBML container; '\x1A\x45\xDF\xA3'. Used by both MKV and WebM.	mkv, webm, mka	video/x-matroska	1A 45 DF A3	0x0	Video
Flash video Flash Video; 'FLV\x01'.	flv	video/x-flv	46 4C 56 01	0x0	Video
MPEG program stream MPEG-1/2 program stream pack header.	mpg, mpeg, vob	video/mpeg	00 00 01 BA	0x0	Video
MPEG transport stream MPEG-TS sync byte 0x47; repeats every 188/204 bytes.	ts, m2ts	video/mp2t	47	0x0	Video
3GPP multimedia 3GPP/3GPP2 video; 'ftyp3g' at offset 4.	3gp, 3g2	video/3gpp	66 74 79 70 33 67	0x4	Video
Advanced Systems Format Microsoft ASF container; GUID 30 26 B2 75 8E 66 CF 11.	asf, wmv, wma	video/x-ms-asf	30 26 B2 75 8E 66 CF 11	0x0	Video
PDF document Portable Document Format; '%PDF'.	pdf	application/pdf	25 50 44 46	0x0	Document
Rich Text Format Rich Text Format; '{\\rtf1'.	rtf	application/rtf	7B 5C 72 74 66 31	0x0	Document
OLE2 Compound Document Microsoft OLE2 compound document; D0 CF 11 E0 A1 B1 1A E1 (DOC, XLS, PPT, MSI, MSG).	doc, xls, ppt, msi, msg	application/x-ole-storage	D0 CF 11 E0 A1 B1 1A E1	0x0	Document
PostScript PostScript; '%!PS'.	ps	application/postscript	25 21 50 53	0x0	Document
Encapsulated PostScript EPS with Binary Header; '%!PS-Adobe'.	eps	application/postscript	25 21 50 53 2D 41 64 6F 62 65	0x0	Document
Forms Data Format PDF form data; '%PDF-1.2' (subset of PDF).	fdf	application/vnd.fdf	25 50 44 46 2D 31 2E 32	0x0	Document
DjVu document DjVu (IFF-based); 'AT&TFORM'.	djvu, djv	image/vnd.djvu	41 54 26 54 46 4F 52 4D	0x0	Document
Mobipocket eBook Mobipocket; 'BOOKMOBI' at offset 60.	mobi, prc	application/x-mobipocket-ebook	42 4F 4F 4B 4D 4F 42 49	0x3C	Document
PalmDoc / PalmDB PalmDOC; 'TexeBook' or other PDB type at offset 60.	pdb	application/vnd.palm	54 65 78 65 42 6F 6F 6B	0x3C	Document
Windows Compiled HTML Help CHM help file; 'ITSF' (LZX-compressed HTML).	chm	application/vnd.ms-htmlhelp	49 54 53 46	0x0	Document
XPS / OpenXPS document XPS is a ZIP-based container with FixedDocument parts.	xps, oxps	application/vnd.ms-xpsdocument	50 4B 03 04	0x0	Document
TrueType font TrueType font; 00 01 00 00.	ttf, ttc	font/ttf	00 01 00 00	0x0	Font
OpenType font (CFF) OpenType with CFF outlines; 'OTTO'.	otf	font/otf	4F 54 54 4F	0x0	Font
TrueType Collection TrueType Collection; 'ttcf'.	ttc	font/collection	74 74 63 66	0x0	Font
WOFF font Web Open Font Format v1; 'wOFF'.	woff	font/woff	77 4F 46 46	0x0	Font
WOFF2 font Web Open Font Format v2; 'wOF2'.	woff2	font/woff2	77 4F 46 32	0x0	Font
Embedded OpenType Microsoft EOT; 'LP' embedded at offset 34 (FontType signature).	eot	application/vnd.ms-fontobject	4C 50	0x22	Font
SQLite 3 database SQLite 3; 'SQLite format 3\x00'.	sqlite, sqlite3, db	application/vnd.sqlite3	53 51 4C 69 74 65 20 66 6F 72 6D 61 74 20 33 00	0x0	Database
dBase III database dBase III DBF; version byte 0x03 (also 0x83 with memo, 0x8B, 0xF5 for FoxPro).	dbf	application/x-dbf	03	0x0	Database
Apache Parquet file Parquet columnar storage; 'PAR1'.	parquet	application/vnd.apache.parquet	50 41 52 31	0x0	Database
Apache Avro object Avro object container; 'Obj\x01'.	avro	application/vnd.apache.avro	4F 62 6A 01	0x0	Database
LevelDB SSTable LevelDB/Snappy-compressed SSTable; 8-byte magic.	ldb, sst	application/x-leveldb	57 FB 80 8B 24 75 47 DB	0x0	Database
LMDB database Lightning Memory-Mapped DB; 'BDB1' magic.	mdb	application/x-lmdb	42 44 42 31	0x0	Database
Microsoft Access (Jet) Access/Jet4 database; 'Standard Jet DB' at offset 4.	mdb	application/x-msaccess	53 74 61 6E 64 61 72 64 20 4A 65 74 20 44 42	0x4	Database
Apple binary property list Binary plist; 'bplist00'.	plist, bplist	application/x-plist	62 70 6C 69 73 74 30 30	0x0	System
ext2/3/4 superblock ext2/3/4 filesystem magic; 0x53EF at offset 1080 (0x438).	img	application/x-ext2	53 EF	0x438	System
Linux swap area Linux swap header 'SWAPSPACE2' at offset 4086.	swap	application/x-swap	53 57 41 50 53 50 41 43 45 32	0xFF6	System
ReiserFS superblock ReiserFS 3.x; 'ReIsEr4Fs' or 'ReIsErFs' at offset 65536.	img	application/x-reiserfs	52 65 49 73 45 72 34 46 73 52 73	0x10040	System
pcapng capture pcapng Section Header Block; '\n\r\r\n'.	pcapng	application/x-pcapng	0A 0D 0D 0A	0x0	System
pcap capture (LE) pcap little-endian; A1B2C3D4 in memory = D4 C3 B2 A1 on disk.	pcap	application/vnd.tcpdump.pcap	D4 C3 B2 A1	0x0	System
pcap capture (BE) pcap big-endian; 'A1B2C3D4' on disk.	pcap	application/vnd.tcpdump.pcap	A1 B2 C3 D4	0x0	System
RPM package RPM Package Manager; ED AB EE DB.	rpm	application/x-rpm	ED AB EE DB	0x0	System
Debian package Debian .deb; Unix ar archive '!<arch>\n' with 'debian-binary' as first member.	deb	application/vnd.debian.binary-package	21 3C 61 72 63 68 3E 0A	0x0	System
Windows Installer (MSI) MSI is an OLE2 compound document (shares the OLE2 magic).	msi	application/x-msi	D0 CF 11 E0 A1 B1 1A E1	0x0	System
Windows Registry hive Registry hive; 'regf'.	hiv	application/x-windows-registry	72 65 67 66	0x0	System
PEM certificate / key PEM container; '-----BEGIN'.	pem, crt, key	application/x-pem-file	2D 2D 2D 2D 2D 42 45 47 49 4E	0x0	Certificate / Key
OpenSSH private key OpenSSH private key; '-----BEGIN OPENSSH...'.	pem, key	application/x-openssh-key	2D 2D 2D 2D 2D 42 45 47 49 4E 20 4F 50 45 4E 53 53 48	0x0	Certificate / Key
DER-encoded ASN.1 DER-encoded ASN.1 sequence; 30 82 (also PKCS#12, X.509 certs).	der, cer	application/pkix-cert	30 82	0x0	Certificate / Key
Java KeyStore Java KeyStore; FE ED FE ED.	jks, keystore	application/x-java-keystore	FE ED FE ED	0x0	Certificate / Key
PGP public keyring PGP public key packet; 0x99 (legacy) length prefix.	pgp, asc	application/pgp-keys	99 01	0x0	Certificate / Key
GPG keybox GPG keybox; FE 04 00 01 header.	kbx	application/pgp-keybox	FE 04 00 01	0x0	Certificate / Key
Nintendo Entertainment ROM iNES ROM; 'NES\x1A'.	nes	application/x-nes-rom	4E 45 53 1A	0x0	ROM / Game
Nintendo 64 ROM N64 ROM; big-endian '80 37 12 40' (also byteswapped / LE variants).	n64, z64	application/x-n64-rom	80 37 12 40	0x0	ROM / Game
SNES ROM (SMC) SNES SMC header; AA BB 04 (also BB AA 04 variants).	smc, sfc	application/x-snes-rom	AA BB 04	0x0	ROM / Game
Game Boy Color ROM Game Boy ROM Nintendo logo at offset 0x104 (CE ED 66 66 …).	gbc, gb	application/x-gb-rom	CE ED 66 66 CC 0D 00 0B 03 73 00 83 00 0C 00 0D	0x104	ROM / Game
Nintendo DS ROM NDS encryption key header at offset 0x07F0 — the game title is at offset 0.	nds	application/x-nds-rom	25 14 21 26 FE 23 26 25	0x0	ROM / Game
Sega Genesis ROM Sega Mega Drive ROM; 'SEGA MEGA' or 'SEGA GENESIS' at offset 0x100.	md, bin, gen	application/x-genesis-rom	53 45 47 41 20 4D 45 47 41	0x100	ROM / Game
Binary glTF (GLB) Binary glTF; 'glTF'.	glb	model/gltf-binary	67 6C 54 46	0x0	3D Model
FBX binary model Autodesk FBX binary; 'Kaydara FBX Binary'.	fbx	application/x-fbx	4B 61 79 64 61 72 61 20 46 42 58 20 42 69 6E 61 72 79	0x0	3D Model
PLY polygon model Stanford PLY; 'ply\n' (text or binary).	ply	application/x-ply	70 6C 79 0A	0x0	3D Model
STL mesh (text) ASCII STL mesh; 'solid ' (binary STL has an 80-byte header).	stl	application/x-stl	73 6F 6C 69 64 20	0x0	3D Model
3D Studio mesh 3ds Max; main chunk 0x4D4D.	3ds	application/x-3ds	4D 4D	0x0	3D Model
BitTorrent metainfo Bencode; 'd8:announce' (start of bencoded dict).	torrent	application/x-bittorrent	64 38 3A 61 6E 6E 6F 75 6E 63 65	0x0	Other
YAML document YAML document start; '---' (text file).	yaml, yml	application/x-yaml	2D 2D 2D	0x0	Other
XML document XML prolog; '<?xml' (also valid for SVG, XHTML, OPML).	xml, svg, xhtml	application/xml	3C 3F 78 6D 6C	0x0	Other
MATLAB .mat v5 MATLAB v5 MAT-file; 'MATLAB 5.0'.	mat	application/x-matlab-data	4D 41 54 4C 41 42 20 35 2E 30	0x0	Other
ESRI Shapefile Shapefile .shp; file code 0x0000270A (big-endian int32 = 9994).	shp	application/x-esrishape	00 00 27 0A	0x0	Other
pcapng capture (alt) pcapng SHB with full 12-byte preamble.	pcapng	application/x-pcapng	0A 0D 0D 0A 1C 00 00 00 4D 3C 2B 1A	0x0	System
Tox protocol save file Tox save; 4 zero bytes then 1F 1B ED 15.	tox	application/x-tox-save	00 00 00 00 1F 1B ED 15	0x0	Other
Minecraft region (.mca) Minecraft region; first 4096 bytes are location table (typically zero-padded).	mca	application/x-minecraft-region	00 00 00 00	0x0	Other
Android Backup Android backup; 'ANDROID BACKUP'.	ab	application/x-android-backup	41 4E 44 52 4F 49 44 20 42 41 43 4B 55 50	0x0	System
OpenEXR image OpenEXR; magic 76 2F 31 01.	exr	image/x-exr	76 2F 31 01	0x0	Image
FITS astronomy image Flexible Image Transport System; 'SIMPLE = T'.	fits	application/fits	53 49 4D 50 4C 45 20 20 3D 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 54	0x0	Image

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