Audio formats split into two families. Lossless formats keep every detail of the recording and make big files. Lossy formats throw away sound the ear is unlikely to notice and make small ones. Converting is mostly a matter of choosing the right family, then the right format within it.
Which format should I choose?
MP3 plays on everything. It is encoded here with LAME at variable bitrate quality 2, typically 170 to 210 kbps, which is transparent for most listeners.
AAC and M4A are the formats Apple devices prefer. Both are encoded at 192 kbps. AAC is slightly more efficient than MP3 at the same size.
Opus is the most efficient lossy codec available and is encoded at 128 kbps, which already sounds excellent. It is ideal for voice and for the web, but older players and car stereos may not support it.
OGG uses the Vorbis codec at quality 5, roughly 160 kbps. It is common in games and open-source software.
WAV is uncompressed 16-bit PCM, the format almost every editor accepts. FLAC is lossless too, but compressed to around half the size of WAV. Use FLAC for archiving music.
Does converting reduce quality?
Converting to WAV or FLAC keeps the audio exactly as it is decoded. Converting to MP3, AAC, M4A, OGG or Opus is lossy. Converting from one lossy format to another loses a little more each time, so start from the best source you have. Converting an MP3 to FLAC does not bring back detail the MP3 removed; it just stores the MP3's sound losslessly.
What happens to my upload?
Conversion runs on our server. Your audio is uploaded over an encrypted connection, converted in Germany and deleted automatically within two hours.
Is there a limit?
Files up to 50 MB are free without an account, within a daily allowance of 20 server jobs (50 with a free account). Pro takes up to 500 MB with no daily cap. Most files convert in a few seconds. Converting an entire music folder from FLAC to MP3 for a phone is easiest in the pipeline builder; you can try it on up to 3 files for free, and larger runs use Pro or credits.
How to convert audio files
- Drop your audio file onto the drop zone. MP3, WAV, FLAC, AAC, OGG, M4A, WMA and Opus are accepted.
- Choose the output format.
- Click Convert.
- Download the converted file.
FAQ
What is the best format for podcasts?
MP3 is the standard for podcast feeds because every app supports it.
Which format is best for editing?
WAV. Every audio editor opens it, and it does not lose quality when you save repeatedly.
Are tags like artist and title kept?
Common tags are usually carried over, but some may be lost between formats. Check them in your player.
Can I convert a video to audio here?
Use Extract Audio or MP4 to MP3 for video files.