Reference

Format and browser support matrix

Sonic Batch reads 15 containers and writes 9. Every combination works in every listed browser — the columns only tell you whether the browser’s own decoder does the work, or whether the self-hosted WebAssembly engine has to.

Your browser

Checking this browser’s capabilities…

Every format

Format capabilities and native decoder support
FormatKindReadWriteChromeFirefoxSafariiOS
MP3 .mp3lossyYesYesNativeNativeNativeNative
WAV .wavuncompressedYesYesNativeNativeNativeNative
M4A .m4alossyYesYesNativeNativeNativeNative
AAC .aaclossyYesYesNativePartialNativeNative
OGG .ogglossyYesYesNativeNativeEngineEngine
Opus .opuslossyYesYesNativeNativePartialPartial
FLAC .flaclosslessYesYesNativeNativeNativeNative
AIFF .aiffuncompressedYesYesPartialPartialNativeNative
M4R .m4rlossyYesYesPartialPartialNativeNative
AMR .amrlossyYesNoEngineEngineEngineEngine
CAF .cafcontainerYesNoEngineEnginePartialPartial
3GP .3gpcontainerYesNoEngineEnginePartialPartial
MOV .movcontainerYesNoPartialEngineNativeNative
MP4 .mp4containerYesNoNativePartialNativeNative
WebM .webmcontainerYesNoNativeNativePartialPartial

What each format is for

Format descriptions and caveats
FormatDescriptionCaveat
MP3 (MPEG-1/2 Audio Layer III)The universal lossy format. Plays on essentially every device made since 1998.
WAV (RIFF PCM)Raw PCM samples with a small header. Perfect fidelity, roughly 10 MB per stereo minute.
M4A (AAC in an MP4 container)Apple’s default AAC container. Better quality than MP3 at the same bitrate.
AAC (raw ADTS stream)Bare AAC frames with no MP4 wrapper — used by broadcast streams and some hardware.Raw ADTS streams decode less reliably than the same audio inside an M4A container.
Ogg VorbisRoyalty-free lossy codec. Standard in game engines, Godot, Unity and Wikimedia.Safari has no Vorbis decoder, so Sonic Batch decodes Ogg with the WASM engine instead.
Opus (in an Ogg container)The best-sounding lossy codec below 128 kbps. Used by WhatsApp, Discord and YouTube.Safari 17+ decodes Opus in CAF/MP4 but not always in Ogg; the WASM engine covers the gap.
FLAC (Free Lossless Audio Codec)Lossless compression, typically 50–60% of WAV size, bit-identical when decoded.
AIFF (Audio Interchange File Format)Apple’s uncompressed PCM format — the WAV equivalent for Logic and Pro Tools.Compressed AIFF-C variants fail in Chrome and Firefox; the WASM engine handles them.
M4R (iPhone ringtone)An M4A file with a .m4r extension. iOS only lists it as a ringtone if it is ≤ 40 seconds.The unusual extension confuses some browsers even though the bytes are ordinary MP4.
AMR-NB (Adaptive Multi-Rate narrowband)Phone-call speech codec: 8 kHz mono, 4.75–12.2 kbps. Decode only — nothing should be created in it.No browser ships an AMR decoder. Sonic Batch decodes it with the WASM engine.
CAF (Core Audio Format)Apple container used by older iOS Voice Memos. Usually holds ALAC, IMA4 or raw PCM.Only Apple browsers open CAF, and only for some inner codecs. The WASM engine handles the rest.
3GP / 3G2 (mobile container)Legacy phone recording container, normally AMR-NB or low-bitrate AAC audio.AMR-in-3GP never decodes natively; the WASM engine extracts the audio track.
MOV (QuickTime container)QuickTime video from iPhone and DSLR cameras. Audio is normally AAC or PCM.Sonic Batch extracts and re-encodes the audio track only; no video is ever produced.
MP4 (ISO base media container)The standard video container. Its audio track is almost always AAC.
WebM (Matroska subset)Open container used by browser recorders and YouTube downloads. Audio is Opus or Vorbis.Safari added WebM playback in 16 but not for every codec combination.

Formats Sonic Batch deliberately will not write

AMR, CAF, 3GP, MOV, MP4 and WebM are read-only here. For the container formats that is because Sonic Batch is an audio tool and writing a video container would be misleading. For AMR it is a judgement call: it is a 1990s narrowband speech codec, and there is no defensible reason to create new files in it when Opus does the same job better at a similar bitrate.

There is also no AI anywhere on this site — no vocal removal, no stem splitting, no acapella extraction, no transcription, no “enhancement”. Every operation here is deterministic: the same input and settings always produce the same output, and nothing is invented.

How the engine works · Privacy detail