Which formats are supported?

You can drop in MP3, WAV, FLAC, M4A, AAC, OGG, Opus, WMA, AIFF, and most video files. Output can be MP3, WAV, FLAC, M4A (AAC), OGG (Vorbis), Opus, or raw AAC.

Can I extract the audio from a video?

Yes. Drop in an MP4, MOV, MKV, or WebM and pick an audio output format — the video track is discarded and only the audio is encoded.

Can I convert several files at once?

Pro members can queue up to 50 files per batch and download everything as a ZIP. Free users convert one file at a time.

Will converting MP3 to FLAC improve quality?

No. Once audio has been encoded to a lossy format like MP3, the discarded detail is gone. Converting to FLAC or WAV makes the file bigger but not better — it only makes sense when a device or editor requires a lossless format.

What does loudness normalization do?

It applies FFmpeg's loudnorm filter targeting −16 LUFS (EBU R128), the common level for podcasts and streaming. It evens out recordings that are too quiet or wildly inconsistent between tracks.

What is the file size limit?

Free users can convert files up to 100 MB. Pro members are limited only by their browser's memory, typically a couple of GB.

Which bitrate should I choose?

128 kbps is fine for speech and podcasts, 192 kbps is a good general default for music, and 256–320 kbps is close to transparent for critical listening. Opus sounds noticeably better than MP3 at the same bitrate.

Convert audio files

Convert audio between MP3, WAV, FLAC, M4A, OGG, Opus, and AAC — or pull the audio track out of a video — with bitrate, sample rate, channel, and loudness controls. 100% in your browser, no upload.

Drop audio or video files, or click to browse

MP3, WAV, FLAC, M4A, OGG, Opus, AAC — or pull the audio out of a video. Up to 100.00 MB, one file at a time on free.

Free plan: 3 conversions a day, one file at a time, up to 100.00 MB. Go Pro for unlimited batch conversion.

What people use it for

Convert a WAV recording to MP3 so it fits in an email or a podcast host's upload limit.
Pull the audio out of an MP4 interview or lecture and save it as MP3 for transcription.
Turn FLAC albums into M4A or MP3 for a phone, car stereo, or older MP3 player.
Downmix a stereo voice recording to mono and drop it to 32 kHz to shrink a speech file.
Normalize loudness across a batch of podcast episodes before publishing.
Convert voice memos (M4A) to WAV for editing in Audacity, Reaper, or a DAW.
Re-encode a big batch of samples to Opus for a game or web project where size matters.

This free online audio converter changes MP3, WAV, FLAC, M4A, AAC, OGG, and Opus files into any other of those formats without uploading a single byte. It runs on ffmpeg.wasm — the same FFmpeg engine desktop audio tools are built on, compiled to WebAssembly — so a WAV to MP3, FLAC to MP3, M4A to MP3, or MP3 to WAV conversion happens entirely on your own machine.

It doubles as an extract audio from video tool: drop in an MP4, MOV, MKV, or WebM and it strips the video track and encodes just the sound, which makes it an easy MP4 to MP3 converter for lectures, interviews, and screen recordings. You control bitrate, sample rate, and channel count, and you can apply EBU R128 loudness normalization so a batch of podcast episodes or voice memos all land at the same perceived volume.

Because nothing is uploaded, there is no queue, no ads, no e-mail, no watermark, and no server that keeps a copy of your recording — which matters for confidential interviews, medical dictation, legal audio, and unreleased music. Free users convert one file at a time, up to 100 MB, three times a day. Pro members convert unlimited files and can queue up to 50 at once, downloading the whole batch as a ZIP.

How it works

1
Drop your files
Drag in audio or video files, or click to browse. Everything stays on your device.
2
Pick a format and quality
Choose the output format, then tune bitrate, sample rate, channels, and optional loudness normalization.
3
Convert and download
ffmpeg.wasm encodes each file locally. Save them one by one, or grab the whole batch as a ZIP.

Frequently asked questions

No. The conversion runs entirely in your browser using an in-browser build of FFmpeg (ffmpeg.wasm). Your files never leave your device.

Want this converter on your website?

Pro members can embed any Minitooler converter on their own site — styled to match, with no branding beyond a small credit link. One iframe, unlimited use, still 100% in the browser.

Unlock embeds — $5/mo

Accent color

Theme

Background

Text color

Width

Height

Embeds are a Pro feature

Upgrade to unlock a customizable iframe snippet you can paste into any website — colors, theme, and size all tuned to match your brand.

Go Pro — $5/mo