Free audio converter

What does an audio converter do?

An audio converter changes a sound file from one format to another, for example WAV to MP3 to make it smaller, or M4A to MP3 so it plays on an older device. The sound stays the same recording; only the way it is stored changes. This one runs in your browser, so your files never leave your device.

Audio formats at a glance

Common conversions and why people make them

• WAV to MP3. A recorded voice-over or podcast take is huge as WAV, about 10 MB per stereo minute. As a 128 kbps MP3 it is around a tenth of that, small enough to email or upload.
• M4A to MP3. iPhone voice memos are M4A. Convert them to MP3 for a transcription service, a web form or a device that doesn’t play M4A.
• MP3 to WAV. Some video editors, phone systems and hardware samplers want WAV. Converting makes the file compatible; it doesn’t improve the sound.
• FLAC to MP3. Make a portable copy of a lossless archive for a phone or a car.
• Anything to OGG. For a web app or game that uses Opus for small, clear speech files.

How to avoid losing quality

Every conversion to a lossy format (MP3, M4A, OGG) throws a little information away. Doing it once is fine; doing it again and again adds up, a bit like photocopying a photocopy. Three rules keep your audio clean:

1. Edit in lossless. Keep the master as WAV or FLAC while you edit, and convert to MP3 or M4A only for the finished file.
2. Don’t convert lossy to lossy without a reason. M4A to MP3 is sometimes needed for compatibility, but each hop costs a little.
3. Don’t expect upgrades. Converting an MP3 to WAV or FLAC makes a bigger file with exactly the same sound. Lossless only helps when the source was lossless.

Bitrate, sample rate and channels

Bitrate sets how much data per second a lossy file uses; 128 kbps MP3 is plenty for speech, 192 kbps or more suits music. Sample rate is how many times per second the sound is measured: 44.1 kHz is the CD standard, 48 kHz the norm for video. Channels are mono or stereo; a single voice recorded with one microphone is effectively mono, so stereo only doubles the size of WAV and FLAC files without adding anything.

The converter lets you set all three: a bitrate for MP3, M4A and OGG, mono or stereo, and a sample rate of 48, 44.1, 22.05 or 16 kHz. Leave them as they are unless a destination asks for something specific. When the format stays the same and nothing changes, Original quality copies the sound untouched.

Which format does the destination want?

• Video editors handle every format here, but WAV avoids surprises and decodes fastest on the timeline.
• Podcast hosts usually ask for MP3; some accept M4A. Check their upload page for a preferred bitrate.
• Learning platforms and help centers play MP3 most reliably in every browser and on phones.
• Phone systems and hardware often need WAV with a specific sample rate and channel count. Read their spec before converting, because a file in the right format but the wrong settings can still be rejected.
• Archives are best kept as FLAC: lossless, smaller than WAV and widely supported.

Audio inside a video?

To get the sound out of an MP4, MOV, WebM or MKV video, use extract audio from video, or MP4 to MP3 for the most common case.

Tips

Name versions clearly

Keep the original file and add the format to the converted file’s name, so you always know which one is the master.

Transcribe from MP3

Speech recognition doesn’t need lossless audio. A small MP3 uploads faster to a transcription tool or the subtitle generator.