How to Convert .opus to MP3 on iPhone (and Android): Free Methods First
An .opus file will not open in most players, editors or car stereos. Here are the free ways to convert it to MP3 on iPhone, Android and a computer, which one to pick, and the mistakes that waste time.
You have a file ending in .opus (very often a WhatsApp voice note called something like PTT-20261001-WA0004.opus) and you need it as an MP3: to play it in the car, attach it to an email, drop it into an editor, or send it to someone whose phone will not open it. This guide lists the free methods first, in the order I would try them, and only mentions an app at the end.
Short answer: on an iPhone, open the free browser converter in Safari, add the file, choose MP3, download. On a computer, VLC or one ffmpeg command does it for free. On Android, check whether your player already opens .opus before converting anything.
What an .opus file is, and why it will not play
Opus is an audio codec designed for speech and low bitrates. It sounds better than MP3 at the tiny sizes a voice message uses, which is why chat apps record in it. The file is usually Opus audio inside an Ogg container, and you may see it named .opus, .ogg or .oga.
The catch is support. MP3 has been everywhere for decades; Opus has not. The iPhone Files app treats an .opus file as a generic document, and many editors, car stereos and older players refuse it. Converting to MP3 trades a slightly larger file for something that opens everywhere.
One thing that does not work: renaming the file to .mp3. That changes the label, not the audio inside, and a player that checks the contents will still refuse it.
Step 0 on iPhone: get the file out of WhatsApp
- Open the chat and long-press the voice message.
- Tap Forward, then the Share icon at the bottom.
- Choose Save to Files and pick a folder you can find again, such as On My iPhone → Downloads.
Need every voice note from one chat? Open the chat, tap the contact or group name, choose Export Chat → Attach Media. The .zip contains each voice note as its own .opus file; tap the .zip in Files to unpack it.
Free method 1 (iPhone): convert in Safari, nothing uploaded
Open the Opus to MP3 converter in Safari. Tap the drop area, choose Choose File (or Browse), pick one or more .opus files from Files, select MP3, and convert. Download each MP3 back to Files, or use Download all.
The conversion runs inside the page on your phone. The audio is not uploaded, there is no account and no file limit from a server. It needs a reasonably current iOS: very old versions of Safari cannot decode Opus, and on those the tool will tell you it failed rather than produce a broken file.
Pick WAV instead of MP3 if the audio is going into an editor or a transcription tool. WAV is uncompressed, so nothing is lost to a second round of compression.
Free method 2 (any computer): VLC
If you can move the file to a Mac or PC (AirDrop, iCloud Drive, email it to yourself), VLC converts it for free:
- Open VLC and choose File → Convert / Stream (Mac) or Media → Convert / Save (Windows).
- Add the .opus file, choose the Audio - MP3 profile.
- Choose where to save, give the file a
.mp3name, and start.
Free method 3 (computer, many files): ffmpeg
If you are comfortable in a terminal, ffmpeg is the fastest way to convert one file or a whole folder:
# one file
ffmpeg -i note.opus -codec:a libmp3lame -q:a 2 note.mp3
# every .opus file in the current folder
for f in *.opus; do ffmpeg -i "$f" -codec:a libmp3lame -q:a 2 "${f%.opus}.mp3"; doneInstall it with brew install ffmpeg on a Mac or winget install ffmpeg on Windows. Audacity also opens .opus files and exports MP3 if you want to trim or boost the audio first.
On Android: check whether you need to convert at all
Android itself understands Opus, so on a recent phone many file managers, music players and VLC for Android play a voice note without any conversion. Try opening it first.
WhatsApp keeps voice notes in Android/media/com.whatsapp/WhatsApp/Media/WhatsApp Voice Notes, in dated subfolders. Most phones' Files app can reach that folder; you can also long-press the voice note in the chat and use Share to send it to another app.
If you do need an MP3 (for a car stereo, an editor, or someone on an older device), the same browser converter works in Chrome on Android, and VLC or ffmpeg on a computer work exactly as above.
What about online converter websites?
They work, and for a song or a podcast clip they are fine. For a voice note, think about it first: the site receives the recording, and voice messages are often the most personal thing on a phone. WhatsApp's end-to-end encryption protects the message in transit, not a copy you upload somewhere. A converter that runs on your own device avoids the question.
If you want the words, not the audio
Many people converting a voice note really want to read it, quote it or search it later. Converting to MP3 does not help with that. Transcribe it instead: see how to turn a voice message into text.
If you convert voice notes often: the app
The browser method is fine for the occasional file. If you do this every week, an app saves the trip through Files: Opus to MP3 Converter (I built it) shows up in the share sheet, so you can send a voice note from WhatsApp straight to it, convert a batch to MP3 or WAV offline, and share the results. It is free on the App Store and on Google Play. For all four of my chat and voice-note tools in one place, see WhatsApp power tools.
The apps mentioned here are independent utilities built by the author. They are not affiliated with, endorsed by, or connected to WhatsApp LLC or Meta Platforms, Inc. WhatsApp is a registered trademark of Meta Platforms, Inc.