Five formats, five jobs
Each output format here is the best choice for a different job:
- MP3 (192 kbps): the universal choice. Every device, app and car stereo plays it.
- M4A (AAC, 192 kbps): slightly better sound than MP3 at the same size, and the native format of iPhone, iTunes and Apple Music. iPhone ringtones are AAC too.
- WAV (16-bit PCM): uncompressed and lossless. For audio editors, DJ and broadcast software, samplers, phone systems (IVR) and anything that demands WAV.
- FLAC: lossless like WAV but typically 40–60% smaller. For archiving music and recordings without losing a bit.
- OGG (Vorbis, quality 5, about 160 kbps): open and royalty-free, widely used by games, game engines, Android notification sounds and some web apps.
What's the difference between lossy and lossless audio?
MP3, M4A and OGG are lossy: they discard sounds you're unlikely to hear to make files about a tenth the size of WAV. WAV and FLAC are lossless: they keep every sample exactly.
Converting is a one-way street for quality. Turning a lossy file into WAV or FLAC preserves it perfectly from then on, but can't restore what the MP3 already threw away. Converting one lossy format into another (say, OGG to MP3) loses a little more each time, though at these bitrates it's very hard to hear. So convert from the best source you have, and avoid ping-ponging between lossy formats.
Can I extract the audio from a video?
The converter also accepts video files: MP4, MOV, WEBM, MKV, AVI and others. It takes the first audio track and converts it to the format you pick, which is handy when you need a WAV of a video's soundtrack for editing, or a FLAC archive of a concert you filmed.
How big are the converted audio files?
For one minute of stereo audio:
- WAV (CD quality, 16-bit/44.1 kHz): about 10 MB.
- FLAC: about 4–7 MB for music, less for speech and quieter recordings.
- MP3 or M4A at 192 kbps: about 1.4 MB.
- OGG at quality 5: about 1.2 MB, depending on the material.
Sample rate and channels
The converter keeps your file's sample rate and channel layout where the output format allows, so a 48 kHz stereo recording stays 48 kHz stereo. Mono recordings stay mono, which is ideal for speech because it halves the size of lossless files compared with stereo.
All processing happens in your browser with ffmpeg. Your audio isn't uploaded anywhere, and you can convert one file after another without waiting for uploads or queues.
Matching the format to where it's going
When in doubt, check what the destination asks for, and pick the simplest format that meets it:
- Podcast hosts: MP3, usually 128–192 kbps.
- Video editors: WAV for audio you'll mix and edit; MP3 or M4A for music beds also works in most editors.
- iPhone ringtones: M4A, renamed to .m4r.
- Unity, Godot and other game engines: OGG for music and long sounds, WAV for short sound effects.
- Archiving CDs, vinyl rips and original recordings: FLAC, so you can always convert to anything later without loss.
- Sending to someone, unsure what they use: MP3.