Audio Converter

How it works

How to convert audio files

Any format to any format in three steps.

1
Add files
Drop audio or video files — or a whole folder — onto the page.
2
Choose a format
Pick MP3, WAV, M4A, FLAC, OGG, AAC or M4R and adjust the quality if you like.
3
Convert & download
Click Convert, preview the results and download them one by one or as a ZIP.

Why ToolCMB

One converter for every audio format

Professional encoders, running privately on your device.

All popular formats

MP3, WAV, M4A (AAC), FLAC, OGG (Opus), raw AAC and M4R ringtones.

Audio from video

Drop an MP4, MOV or WebM video and save its soundtrack as MP3 or any other format.

Full control

Bitrate, VBR, bit depth, sample rate and mono/stereo — or just keep the defaults.

Tags preserved

Title, artist, album, year, track number and cover art move to the new file.

Batch conversion

Convert up to 100 files in one go, with a size estimate for each one.

Listen before saving

Play the result and switch between original and converted file instantly.

Private by design

Files are converted in your browser and never uploaded anywhere.

Free

No account, no watermark, no file size limits.

Which audio format should you choose?

MP3 is the safest choice: it plays on every phone, computer, car stereo and website. M4A (AAC) sounds a little better at the same size and is the native format of Apple devices. OGG (Opus) is the most efficient format and ideal for the web and for voice.

WAV and FLAC are lossless. WAV is uncompressed and best for editing software; FLAC keeps exactly the same sound in a file that is roughly half the size — perfect for archiving music. Converting an MP3 to WAV or FLAC does not restore lost quality, it just stores the MP3’s sound without further loss.

Converting from one lossy format to another (for example OGG to MP3) always loses a little quality. Choose a bitrate at least as high as the original — 192 kbps or more is a safe default for music.

Audio formats compared

Format	Type	Typical size per minute	Best for
MP3	Lossy	1–2.4 MB	Everything, maximum compatibility
M4A (AAC)	Lossy	1–2 MB	iPhone, iTunes, YouTube
OGG (Opus)	Lossy	0.4–1.5 MB	Web, games, voice
FLAC	Lossless	5–6 MB	Archiving music in full quality
WAV	Uncompressed	10.1 MB (16-bit stereo)	Editing, DAWs, CDs
M4R	Lossy (AAC)	max. 40 seconds	iPhone ringtones

Tips

Only need MP3s? The dedicated WAV to MP3, M4A to MP3 and FLAC to MP3 pages have presets for that.
Making files smaller rather than changing format? Try the MP3 Compressor.
Want only part of a song? Cut it first with the Audio Cutter.
Check the codec, bitrate and tags of any file with the Audio Metadata Viewer.

FAQ

Frequently asked questions

Can’t find your answer? Contact us — we reply quickly.

Which formats can I convert?

You can open MP3, WAV, M4A, AAC, FLAC, OGG, Opus, WebM and the sound of MP4/MOV videos, and save as MP3, WAV, M4A, AAC, FLAC, OGG (Opus) or M4R.

Is the converter really free?

Yes, completely free with no sign-up, no watermark and no limits on the number of files.

Are my files uploaded?

No. The conversion runs in your browser with WebAssembly encoders. Your files never leave your device.

How do I extract audio from a video?

Drop the MP4, MOV or WebM video onto the page, choose MP3 (or another format) and click Convert. Only the soundtrack is saved.

Will converting reduce the quality?

Converting to WAV or FLAC is lossless. Converting to MP3, M4A or OGG compresses the audio; at 192 kbps and above the difference is inaudible for most people.

Can I convert many files at once?

Yes. Add up to 100 files (or a folder) and convert them in one go. Download them individually or as a single ZIP file.

Why does OGG use Opus?

Opus is the modern codec for Ogg files: it sounds better than Vorbis or MP3 at the same size and is supported by all current browsers, Android and VLC.