Convert audio files online


(It must be a valid sample rate value that target format supports.)
Conversion Results:
# Output File Source File Action

NEW! Download Audio Converter for Android to convert audio files on your phone offline.

Steps:

1. Click "Choose File" button to select a file on your computer. You can also click the dropdown button to choose online file from URL, Google Drive or Dropbox. The source file can also be video format. Video and audio file size can be up to 200M.

2. Choose target audio format. The target audio format can be WAV, WMA, MP3, OGG, AAC, AU, FLAC, M4A, MKA, AIFF, OPUS or RA.

3. Click "Convert Now!" button to start conversion. It will automatically retry another server if one failed, please be patient while converting. The output files will be listed in the "Conversion Results" section. Click icon to show file QR code or save file to online storage services such as Google Drive or Dropbox.

Compare OPUS with M4A:
Name OPUS M4A
Full name Opus Audio Format Audio-only MPEG-4
File extension .opus .m4a
MIME audio/opus video/mp4
Developed by IETF codec working group International Organization for Standardization
Type of format Audio Media container
Introduction Opus is a lossy audio coding format developed by Xiph and standardized by the IETF, designed to efficiently code speech and general audio in a single format, while remaining low-latency enough for real-time interactive communication and low-complexity enough for low end ARM3 processors. MPEG-4 Part 14 or MP4 is a digital multimedia container format most commonly used to store video and audio, but can also be used to store other data such as subtitles and still images. M4A stands for MPEG 4 Audio and is a filename extension used to represent audio files.
Technical details Opus supports constant and variable bitrate encoding from 6 kbit/s to 510 kbit/s, frame sizes from 2.5 ms to 60 ms, and five sampling rates from 8 kHz (with 4 kHz bandwidth) to 48 kHz (with 20 kHz bandwidth, the human hearing range). An Opus stream can support up to 255 audio channels, and it allows channel coupling between channels in groups of two using mid-side coding. Audio-only MPEG-4 files generally have a .m4a extension. This is especially true of non-protected content. M4A is often compressed using AAC encoding (lossy), but can also be in Apple Lossless format.
Associated programs FFmpeg, AIMP, Amarok, cmus, foobar2000, Mpxplay, MusicBee, SMplayer, VLC media player, Winamp Windows Media Player, RealPlayer, MPlayer, Media Player Classic, VLC Media Player, K-Multimedia Player
Sample file sample.opus sample.m4a
Wiki OPUS on Wikipedia M4A on Wikipedia