Audacity as shipped reads and writes uncompressed WAV and AIFF plus a short list of compressed formats — and on Windows and Mac that list includes MP3, even though one of Audacity's own official pages leaves MP3 out of it.
That disagreement is why this question produces contradictory answers everywhere you look. Below is what each manual page actually says, which page to follow when they clash, and what to do with a file that is on neither list.
The formats, at a glance
The Importing Audio page states the shipped import list directly:
"The audio formats importable by Audacity with the File > Import > Audio command, as shipped are:"
"For uncompressed audio: most WAV and AIFF files including all PCM variants can be imported into Audacity"
"Compressed audio: MP3, Ogg Vorbis, FLAC and MP2 can be imported into Audacity."
| Format | Works without FFmpeg? | What the manual says |
|---|---|---|
| WAV, AIFF | Yes, both directions | "most WAV and AIFF files including all PCM variants" |
| Ogg Vorbis, FLAC, MP2 | Yes, both directions | listed as shipped compressed formats in the FAQ |
| MP3 | Import yes; export uses LAME, built in on Windows and Mac | see the next section |
| AC3, M4A, MP4, WMA | FFmpeg required, with one Mac exception | "You can install the optional FFmpeg library to import a much larger range of audio formats" |
| Opus | Through FFmpeg | "Audacity does not natively support Opus" |
| Files with no header (RAW, VOX ADPCM) | Yes, via File > Import > Raw Data | "you can normally import them using File > Import > Raw Data" |
| LOF (list of files) | Yes | "supported if the list is correctly formatted and contains supported files" |
The MP3 contradiction, and which page to follow
The FAQ on opening and saving files gives its own shipped-format list, and MP3 is not on it:
"Audacity as shipped can import or export the following audio formats:"
"Uncompressed audio formats: most WAV and AIFF files including all PCM variants"
"Compressed audio formats: Ogg Vorbis, FLAC and MP2"
Three other pages point the other way. Importing Audio names MP3 in its shipped compressed list, quoted above. The LAME FAQ is explicit about export:
"The software patent on LAME encoding library has expired, so now the LAME library for MP3 export is built-in with Audacity for Windows and Mac. Linux users will still need to download and install the free and recommended LAME third-party encoder to export MP3 files from Audacity."
And the Export Formats page describes MP3 among its compressed format types rather than its FFmpeg format types.
The working rule: on Windows and Mac, MP3 goes in and out of Audacity with nothing extra installed. On Linux, import is fine but MP3 export still needs LAME installed separately. That reading comes from the pages dedicated to MP3 and to LAME, which agree with each other; the general FAQ is the outlier.
One thing that cannot settle it: page dates. Every page in the manual we checked carries the same footer line, "This version created on 2026-09-02", so there is no newer-page tiebreaker here. If you found a tutorial telling you to download LAME before you can export MP3 on Windows, that instruction is contradicted by the LAME FAQ above.
What installing FFmpeg adds
The optional library widens the list considerably. From Importing Audio:
"You can install the optional FFmpeg library to import a much larger range of audio formats including AC3, M4A, MP4 and WMA (if the files are not DRM-protected to work only in particular software). FFmpeg will also import audio from most video files or DVDs that are not DRM-protected."
Note the exact scope of that last sentence: it promises audio from video files. The manual does not describe Audacity handling the video track itself.
It is not bundled for a legal reason, stated on the FFmpeg FAQ:
"Because of software patents, Audacity cannot include the FFmpeg software or distribute it from its own websites."
That page sends you to the Audacity Support site for the installation details, so check the official documentation for the current download and version requirements rather than trusting a third-party mirror.
There is also an asymmetry worth knowing before you plan a workflow around it. The Custom FFmpeg Export page states: "FFmpeg can only export about two-thirds of the formats that it can import." Being able to open something is not proof you can save it back out.
The Mac exception almost nobody mentions
The FAQ page adds a qualifier that the Importing Audio page does not carry:
"You can install the optional FFmpeg library to import and export a much larger range of audio formats including AC3, M4A, MP4 and WMA (on Mac only, Audacity can import unprotected M4A, MP4 and MOV files without FFmpeg)."
Both qualifiers matter. It applies on Mac only, and only to unprotected files. If a file is DRM-protected, the manual gives one route: "If an audio file you want to import is DRM-protected (for example, an older iTunes M4P file), first burn it to an audio CD in the application that is licensed to play it. Then rip the CD track to WAV or AIFF."
What to do when your file is not on the shipped list
You have two paths, and the right one depends on how often you will need it.
- Install FFmpeg if you regularly work with M4A, WMA, AC3 or audio pulled from video. It is a one-time setup and it also unlocks Opus and the custom exporter.
- Convert the file first if this is a one-off. Handing Audacity a format from its shipped list sidesteps the library question entirely — and it also sidesteps a related trap, since an MP3 imported through FFmpeg loses its "Artist" and "Year" tags, which the built-in importer keeps.
For the single most common case, an M4A recording from a phone or a voice memo, converting to MP3 before import takes seconds:
Try it right here
Runs in your browser. Your file is not uploaded anywhere.
This runs in your browser tab, so the audio is never uploaded anywhere. Other Clapr tools cover the rest of the shipped list — WAV to MP3 and FLAC to MP3 among them. If Audacity is refusing an MP4 specifically, see why Audacity cannot import MP4.
Two special cases the manual calls out separately: files with no header information "such as RAW or VOX ADPCM" go through File > Import > Raw Data, but recorder files do not — "WAV files from portable recorders may contain proprietary compressed audio. These should not be imported as Raw Data, but by installing the FFmpeg library."
Gotchas the format list does not tell you
- The export format table is not complete. The Export Formats page does not cover Opus or WavPack, yet both have full option pages in the manual. So a user checking that one table can conclude Opus export is unavailable when a dedicated Opus export dialog exists.
- "Natively" is doing real work in the Opus sentence. The FAQ says "Audacity does not natively support Opus. If FFmpeg is installed, Audacity will attempt to use FFmpeg for importing Opus files." The Opus export page names the format choice as "Opus (OggOpus) Files (FFmpeg)" — supported, just not natively.
- Ogg import ignores your bit depth setting. Per the manual: "OGG is unusual in that it will always import at 16-bit resolution using the standard OGG Vorbis importer, irrespective of Default Sample Format." It can be imported at 32-bit through FFmpeg.
- Two formats on the list have a hard ceiling. "WAV and AIFF files are limited to a maximum size of 4GB (this is a general restriction and not an Audacity one)." For longer material the manual points to RF64 or CAF headers under "Other uncompressed files", whose size limit it gives as "about 16 exabytes".
FAQ
Does Audacity support MP3 without installing anything? On Windows and Mac, yes — the LAME FAQ states LAME is now built in on both. On Linux you still need to install LAME to export MP3. Import works regardless.
Why does the Audacity FAQ list not include MP3? That page's shipped compressed list reads "Ogg Vorbis, FLAC and MP2". Three other manual pages — Importing Audio, Export Formats and the LAME FAQ — put MP3 in the shipped set, and all the pages share the same footer date, so follow the format-specific pages.
Can Audacity open M4A or MP4 files? With FFmpeg installed, yes, for the audio. On Mac there is an exception: unprotected M4A, MP4 and MOV can be imported without FFmpeg. DRM-protected files are not importable either way.
Can Audacity import video files? The manual says FFmpeg "will also import audio from most video files or DVDs that are not DRM-protected". It describes importing the audio, not editing video.
Why can I import a format but not export it? The Custom FFmpeg Export page explains it plainly: "FFmpeg can only export about two-thirds of the formats that it can import." It also warns that some combinations "might result in zero-byte or invalid files".
Format lists quoted from the official Audacity Manual, checked 16 September 2026. More capacity and format ceilings are collected in our limits guides.
