Common Audio Formats Compared (2026 Guide)
There are dozens of audio formats, but a handful cover almost everything you will encounter. This guide compares them side by side so you can pick the right one for listening, sharing, editing or archiving — and know when a conversion is worth it.
First, containers vs codecs
A codec is the method used to compress (encode) and decompress (decode) audio — for example MP3, AAC, FLAC or Opus. A container is the file format that wraps the encoded audio together with metadata — for example MP4/M4A, OGG, WAV or Matroska. Some names refer to both (MP3, FLAC). Others are containers that can hold several codecs: an .m4a can hold AAC or ALAC; an .ogg can hold Vorbis, Opus or FLAC; a .wav is nearly always uncompressed PCM. When a file won’t play, the problem is often the codec inside rather than the extension outside.
The quick comparison
| Format | Type | Size (per min, typical) | Compatibility | Best for |
|---|---|---|---|---|
| MP3 | Lossy | 1–2.4 MB | Universal | Sharing, cars, older devices |
| AAC / M4A | Lossy | 1–2 MB | Excellent on modern devices | Apple devices, video, streaming |
| Opus | Lossy | 0.2–1.5 MB | Browsers, Android, chat apps | Voice, calls, low bitrates |
| Vorbis (OGG) | Lossy | 0.8–2 MB | Browsers, Android, games | Games, open-source projects |
| WMA | Lossy | 1–2 MB | Mostly Windows | Legacy Windows libraries |
| WAV | Uncompressed | ~10 MB | Universal on computers | Recording, editing |
| AIFF | Uncompressed | ~10 MB | Apple and pro audio | Recording on Mac |
| FLAC | Lossless | 5–7 MB | Very good (not older Apple apps) | Archiving, hi-fi listening |
| ALAC | Lossless | 5–7 MB | Apple ecosystem | Lossless on iPhone/Mac |
MP3
The veteran. Introduced in 1993, MP3 is less efficient than modern codecs but plays on literally everything — which is why it remains the default choice for sharing. Patents expired in 2017, so it is completely free. Use 128 kbps for speech and 192–320 kbps for music. If a device rejects your other files, converting to MP3 almost always fixes it.
AAC (usually .m4a)
MP3’s successor, standard on Apple devices, YouTube and streaming video. Better quality than MP3 at the same bitrate, especially below 128 kbps. Plays on all modern phones, computers and browsers; older car stereos and cheap players may not support it. See our explainer What is AAC? and the M4A to MP3 converter for compatibility fixes.
Opus
The most efficient general-purpose lossy codec available today and fully open. Opus sounds good for speech at 16–32 kbps and for music at 96–128 kbps, with very low latency, which is why WhatsApp, Discord, Zoom-style apps and WebRTC use it. It’s usually stored in .ogg, .opus or .webm files. Support outside browsers and Android is improving but still inconsistent — convert with OGG to MP3 when needed.
Vorbis (OGG)
Opus’s predecessor from the Xiph.Org Foundation, released in 2000 as a patent-free alternative to MP3. Widely used in video games, open-source software and Wikipedia audio. Good quality, but limited support in car stereos and some Apple apps.
WMA
Microsoft’s Windows Media Audio from the late 1990s. Still found in old Windows Media Player libraries. Support outside Windows is limited, and it has largely been superseded by AAC and MP3.
WAV and AIFF
Uncompressed PCM audio in a Microsoft (WAV) or Apple (AIFF) container. Universally used in recording and editing because there is no decoding overhead and no quality loss. Files are huge, so convert to MP3 or AAC for distribution with WAV to MP3, but keep the originals as masters.
FLAC
The open-source lossless standard: about half the size of WAV with identical audio, plus excellent tagging and cover-art support. Ideal for archiving CDs and for hi-res downloads. Most modern players support it; if yours doesn’t, FLAC to MP3 at 320 kbps gives transparent quality in a quarter of the space.
ALAC
Apple’s lossless codec, usually inside an .m4a file. Equivalent to FLAC in compression and quality, with native support across Apple devices. Since 2011 it has been open source.
Which format should you use?
- Sharing with anyone, anywhere: MP3 at 192 kbps.
- Apple-centric library: AAC 256 kbps or ALAC.
- Voice messages and calls: Opus.
- Recording and editing: WAV or AIFF.
- Archiving music: FLAC (or ALAC for Apple users).
- Video soundtracks: AAC — and use MP4 to MP3 to extract audio when you need it.
Conversion rules of thumb
- Convert from lossless whenever possible.
- When transcoding lossy → lossy, use an equal or higher bitrate. Our bitrate guide has a cheat sheet.
- Converting lossy → lossless never restores quality.
- Keep originals until you have checked the converted files.
Every converter on this site runs locally in your browser, so you can try formats freely without uploading anything.