Free Lossless Audio Codec (FLAC)

Created

  • 2024-03-01

Last Updated

  • 2026-10-09

Available Formats

FLAC Application Metadata Block IDs

Registration Procedure(s)

  • First Come First Served

Reference

  • RFC 9639: Free Lossless Audio Codec (FLAC)

Available Formats

Application ID ASCII Rendition (If Available) Description Reference Change Controller
0x41544348 ATCH FlacFile FlacFile; RFC 9639 IETF
0x42534F4C BSOL beSolo RFC 9639 IETF
0x42554753 BUGS Bugs Player RFC 9639 IETF
0x43756573 Cues GoldWave cue points RFC 9639 IETF
0x44495343 DISC Red Book CD-DA LBA track layouts, TOC/CUE structures, verification logs, and additional data for audio preservation Angel Garcia Rodriguez Angel Garcia Rodriguez
0x46696361 Fica CUE Splitter RFC 9639 IETF
0x46746F6C Ftol flac-tools RFC 9639 IETF
0x4D4F5442 MOTB MOTB MetaCzar RFC 9639 IETF
0x4D505345 MPSE MP3 Stream Editor RFC 9639 IETF
0x4D754D4C MuML MusicML: Music Metadata Language RFC 9639 IETF
0x52494646 RIFF Sound Devices RIFF chunk storage RFC 9639 IETF
0x5346464C SFFL Sound Font FLAC RFC 9639 IETF
0x534F4E59 SONY Sony Creative Software RFC 9639 IETF
0x5351455A SQEZ flacsqueeze RFC 9639 IETF
0x54745776 TtWv TwistedWave RFC 9639 IETF
0x55495453 UITS UITS Embedding tools RFC 9639 IETF
0x61696666 aiff FLAC AIFF chunk storage foreign-metadata; RFC 9639 IETF
0x696D6167 imag flac-image RFC 9639 IETF
0x7065656D peem Parseable Embedded Extensible Metadata RFC 9639 IETF
0x71667374 qfst QFLAC Studio RFC 9639 IETF
0x72696666 riff FLAC RIFF chunk storage foreign-metadata; RFC 9639 IETF
0x74756E65 tune TagTuner RFC 9639 IETF
0x77363420 w64 [1] FLAC Wave64 chunk storage foreign-metadata; RFC 9639 IETF
0x78626174 xbat XBAT RFC 9639 IETF
0x786D6364 xmcd xmcd RFC 9639 IETF

Contact Information

Name Contact URI Last Updated
Angel Garcia Rodriguez angelgar&gmail.com 2026-10-09

Footnote

[1]

The value is "w64 " with a single space in order to be four bytes.