Convert audio files in your browser
TubePull Audio Converter changes an audio file from one format to another without uploading it. Open an MP3, WAV, FLAC, OGG, Opus, M4A, AAC, AIFF or WMA file, choose the format you need and download the new file. The conversion runs on your own device, inside the browser tab, so the file never goes to TubePull or to any other server. The converter is free and needs no account. It saves MP3, M4A, FLAC, WAV, OGG (Vorbis), Opus and M4R, the file type an iPhone uses for ringtones. You can convert a whole file or only a section of it.
Output formats and their settings
| Output | Settings | Pick it when |
|---|---|---|
| MP3 (default) | Constant bitrate of 128, 192 or 320 kbps, 192 unless you change it. Sample rate up to 48 kHz; surround is mixed to stereo. | The file has to play on any phone, car stereo or old player |
| M4A | AAC audio. AAC from an M4A or AAC file is copied as it is; anything else is encoded at 192 kbps. | You want a small file for Apple devices and most modern players |
| M4R | The same AAC audio as M4A, saved with the .m4r extension | You want a custom iPhone ringtone |
| FLAC | Lossless, 16-bit, at the source's sample rate and channel count | You are archiving music and want it smaller than WAV |
| WAV | Uncompressed 16-bit PCM at the source's sample rate and channel count | An editor or other program accepts nothing else |
| OGG (Vorbis) | 192 kbps, sample rate up to 48 kHz | A game, app or player asks for Ogg |
| Opus | 128 kbps at 48 kHz | Speech, podcasts and voice notes in a compact file |
Every format except MP3 keeps the source's channel count, unless the compatibility engine described below makes an Opus file, which it mixes down to stereo. The new file is named after the original with "-converted" added, such as song-converted.flac.
Popular conversions
- FLAC to MP3: makes a lossless album small enough for a phone or a car. Use 320 kbps for music you listen to closely, or 192 kbps to save space. Keep the FLAC files as your archive copy.
- WAV to MP3: CD-quality WAV uses 1,411 kbps, so a 192 kbps MP3 is about one seventh of the size, and a 128 kbps MP3 about one eleventh.
- M4A to MP3: for players and programs that don't read AAC. Both formats are lossy, so pick 192 or 320 kbps to keep the second encode clean.
- WMA to MP3: older Windows Media Audio files become MP3 files that play everywhere. WMA files with DRM can't be converted.
- OGG or Opus to MP3: voice messages saved from chat apps are often Opus audio in an .ogg or .opus file, which many desktop players won't open.
- WAV or AIFF to FLAC: lossless compression that keeps every sample of a 16-bit file in a smaller file.
Make an iPhone ringtone (M4R)
An M4R file holds AAC audio in an MPEG-4 file. It is an M4A with another extension. When your source is already AAC, as most M4A files are, the converter copies that audio into the M4R without encoding it again. Audio in any other format is encoded as AAC at 192 kbps. Type a start and an end time to choose the part you want. If the M4R would be longer than 40 seconds, a warning tells you that iPhone ringtones are limited to 40 seconds, which is the limit for ringtones copied from a computer. The convert button stays on, so you can still save a longer file. Apple's GarageBand app makes ringtones of up to 30 seconds, so 30 seconds or less is the safest length. To install the ringtone, connect the iPhone to a computer and drag the .m4r file onto the iPhone in the Finder on a Mac, or in iTunes on Windows. Then choose it in Settings, under Sounds & Haptics and Ringtone.
Does converting lose quality?
That depends on the formats on both sides.
- Lossy to lossy (MP3, AAC, Vorbis and Opus to one another) encodes the sound again, which adds a small loss each time. A higher bitrate can't bring back what the source already lost, so convert from a FLAC or WAV original when you have one. Copying AAC into M4A or M4R is the exception: it loses nothing.
- Lossy to lossless (for example MP3 to WAV) keeps the sound exactly as it is, but no better, in a much larger file. It helps only when a program won't open the lossy file.
- Lossless to lossless (WAV, AIFF and FLAC) keeps every sample of a 16-bit source. A FLAC made from a 16-bit WAV converts back to a WAV with the same sample rate, channel count and samples. TubePull tests this with generated WAV files from 8 to 192 kHz and from 1 to 8 channels.
WAV and FLAC files from this converter are always 16-bit, the bit depth of a CD. A 24-bit or 32-bit float source is reduced to 16-bit, which is fine for listening. If you need to keep 24-bit audio, keep the original file. WAV and FLAC keep the source's sample rate, and M4A and M4R keep it up to 96 kHz.
Tags and cover art
Tags such as title, artist and album are copied into MP3, M4A, M4R, FLAC, OGG and Opus files exactly as they are written in the source, and the converter adds no tags of its own. The cover image is copied into MP3, M4A, M4R and FLAC with its bytes unchanged. OGG files, and Opus files made by the compatibility engine, come out without the cover. WAV files get no tags at all.
Convert part of a file or one of its tracks
The Start and End fields are optional. Leave both empty to convert the whole file, or fill in one or both to keep a section, such as the chorus for a ringtone or one talk from a long recording. Times can be seconds (95), minutes and seconds (1:35.5) or hours, minutes and seconds (0:01:35.250), and the shortest section is 0.1 seconds. When AAC is copied into M4A or M4R, each cut moves to the nearest AAC frame, so it can be a few hundredths of a second from the time you typed. A file with more than one audio track shows a track list with each track's number, language, codec and channel count. The converter starts with the first track and converts only the one you pick.
What happens to your file
The file is opened and converted inside the browser tab. Nothing from the file, including its name and tags, is sent over the network; the page only fetches its own program files from TubePull. Your browser's own audio codecs (WebCodecs) usually make the Opus and M4A files. MP3, WAV, FLAC, OGG and M4R files come from a compatibility engine, FFmpeg compiled to WebAssembly (ffmpeg.wasm), which also takes over when your browser can't read a file, as with WMA. Its download is about 32 MB, made once on the first conversion that needs it; after that the browser keeps it cached. Versions, licenses and source code links are on the licenses page.
Limits and tips
- The converter takes one file at a time.
- File size is limited only by your device's memory. On a phone, files over 500 MB bring up a warning, which you can dismiss and carry on.
- Before it starts, the compatibility engine estimates the output size and refuses anything over about 1.5 GB, which is roughly two hours of 48 kHz stereo WAV. A FLAC output is estimated from the size of the source file.
- Files that are damaged, protected with DRM or have no audio track can't be converted, and the page tells you which.
- An audio-only file with the .mp4 extension isn't accepted here. Open it in Video to MP3 instead.
Have a video or a link instead?
This converter takes audio files only. If you choose a video, the page says so and links to Video to MP3, which saves the soundtrack of a video file as MP3, WAV, FLAC, OGG, Opus or M4A. If the audio is still online, paste the link into the TubePull downloader. To cut a video, use the Video Trimmer, or see all the free video tools.