# Audio converter: change any file's format

Change any audio or video file into MP3, WAV, M4A, FLAC, OGG, or Opus.

## Lossy or lossless

Audo's online audio converter turns audio (WAV, MP3, M4A, AAC, FLAC, OGG, Opus, WebM, AIFF) and video (MP4, MOV, MKV, WebM, AVI) of up to 100 MB into MP3, WAV, M4A, FLAC, OGG, or Opus without an account, free for the first hour of each file, 10 times a day, with no sign-up. Most files take seconds: a 3-minute one usually converts in about 4. To make a file smaller, use Compress audio, and for a video's sound in the format you choose, Extract audio from video.

Lossy formats save space by leaving out detail people rarely hear. MP3 plays on almost everything. M4A, which holds AAC sound, suits Apple devices and usually sounds a little better than MP3 at the same size. OGG and Opus are open formats, small, and good for the web and for speech.

Lossless formats keep every detail. WAV is uncompressed, about 10 MB a minute at CD quality, and it's the format editors and many apps expect. FLAC keeps every detail in a smaller file. Turning a lossy file into a lossless one doesn't bring detail back: it only makes the file bigger.

Tool: Convert (`convert_audio`). The same tool's other pages: https://audo.ai/mp4-to-mp3.md, https://audo.ai/extract-audio-from-video.md, https://audo.ai/m4a-to-mp3.md, https://audo.ai/wav-to-mp3.md, https://audo.ai/mp3-to-wav.md, https://audo.ai/mov-to-mp3.md, https://audo.ai/ogg-to-mp3.md, https://audo.ai/flac-to-mp3.md, https://audo.ai/webm-to-mp3.md, https://audo.ai/aac-to-mp3.md, https://audo.ai/mp4-to-wav.md, https://audo.ai/m4a-to-wav.md, https://audo.ai/mp3-to-ogg.md, https://audo.ai/compress-audio.md, https://audo.ai/mkv-to-mp3.md. Price: 1 credit a minute — $0.01/min ($0.60/hr), with no subscription — of input for whole files, charged only when a job succeeds.

## Free API

```bash
curl -F file=@episode.wav -F format=mp3 https://audo.ai/api/try/convert -D response.headers -o response.body
```

Read response.headers and response.body before naming media. Handle 202, 200 JSON and errors with the complete response client at https://audo.ai/docs/api#responses.

Free for the first hour of each file, 10 times a day per person, with no key or account. Uploads up to 100 MB, 2 at once from one address. The response is the result itself; a job that runs longer than about 30 seconds returns 202 with a link to check on it. With an API key (`-H "Authorization: Bearer $AUDO_API_KEY"`), omitting free runs the whole file with credits if the balance covers it, otherwise the free portion if quota remains. Set free=true to prohibit spending; for paid whole files use free=false with an approved positive max_credits. A free result cut short comes with finishUrl (and the Audo-Finish-Url header when the response is the file itself): give it to the person, who pays there (from $5, no sign-up), and the whole file runs; keep checking the status link, whose finishedBy names the whole-file job and its own status link. Details: https://audo.ai/docs/api.md

## Options

Form fields with the same names as the MCP tool's inputs:

- `format`: The format to convert to: mp3, wav, m4a, flac, ogg, or opus. Default mp3.
- `bitrate_kbps`: The bitrate for mp3, m4a, ogg, or opus, in kbps (16 to 320), such as 128. Default: chosen for the format.
- `sample_rate`: The sample rate in Hz, such as 44100. Default: the input's.
- `channels`: mono or stereo. Default: the input's.

## Languages

Any language: it works on the sound, not the words.

## From an assistant (MCP)

Add https://audo.ai/mcp and sign in (setup for each assistant: https://audo.ai/setup.md). The tool is `convert_audio`:

> Converts a file to another audio format, or pulls the audio out of a video. Use it when the person needs MP3, WAV, M4A, FLAC, OGG, or Opus. Set free to true to do the first hour at no cost, up to 10 times a day; otherwise it costs 1 credit a minute. Returns job_id; then call get_job.

Example: "Use Audo to convert episode.wav to a 128 kbps mono MP3."

## More

- Every tool: https://audo.ai/llms.txt
- OpenAPI: https://audo.ai/api/openapi.json
- This page for people: https://audo.ai/audio-converter