How to Convert Voice Memos, Voicemails, Telegram and Signal Voice Messages to MP3 on iPhone (Offline, No Upload)

Most of what we have written about audio conversion on iPhone has been about WhatsApp, because its .opus voice notes are the file nobody can open. But the same conversion problem turns up in four other places that have nothing to do with WhatsApp: a Voice Memo you need to send to someone's old car stereo, a voicemail you want to keep as evidence or attach to an email, a Telegram voice message, and a Signal voice message. Each of those hands you a file that is perfectly standard and still gets refused somewhere.

This is a guide to getting each of those four out of its app and into MP3 or WAV on the phone itself, using Voice Note Audio Converter (listed on the App Store as Opus to MP3 Converter), with an honest section on when you should not bother converting at all. It is iPhone-only in the steps below; the Android version works similarly but the share sheet and file paths differ.

First, do you actually need to convert?

Voice Memos and iPhone voicemail record in .m4a, which is AAC audio in an MPEG-4 container. Almost every modern phone, computer, email client and browser plays .m4a without complaint. If your only goal is to send a Voice Memo to another iPhone user or to someone on a laptop made in the last decade, share the .m4a and stop reading. Converting it to MP3 gains nothing and loses a little quality.

The cases where conversion is genuinely needed are narrower and very real:

• Older hardware. Car stereos with a USB port, cheap MP3 players, some conference phones and older Android devices often play MP3 and nothing else.
• Attachment and upload rules. Some web forms, learning platforms and HR or legal portals accept .mp3 or .wav only and reject .m4a and .ogg outright.
• Editing and transcription. Audio editors and speech-to-text tools are happiest with uncompressed WAV. Feeding them a compressed .m4a works but adds a decode step, and some refuse .ogg entirely.
• Telegram and Signal voice messages. These are .ogg (Opus) or .m4a depending on the app and platform, and .ogg is the one that iOS cannot play in Files or Music at all.
• Keeping a copy that will still open in ten years. MP3 and WAV are the two formats you can be reasonably sure will open anywhere, which matters for a voicemail you are keeping for a dispute.

What the converter does with these files

The app's input list covers all four sources: .m4a and .aac for Voice Memos and voicemail, .ogg and .oga for Telegram and Signal, plus .opus, .mp3, .wav, .caf, .aiff, .flac, .amr and .3gp. Output is MP3 at 128 kbps or 16-bit WAV. Conversion happens on the phone: the file is decoded and re-encoded locally, nothing is uploaded, no account is needed, and it works with the network off. You can pick a batch of files in one go and each result gets its own Share button. It is free with a small banner ad and a one-time Remove Ads purchase for $0.99; there is no watermark, file limit or subscription.

Two things it is not: it is not a recorder, and it is not a transcriber. If you want the words rather than the audio, the sister app Voice Note to Text does that on-device instead.

1. Voice Memos to MP3

• Open Voice Memos, tap the recording, then tap the three-dot (More) button and choose Share.
• In the share sheet, pick the converter if it is listed, or choose Save to Files and put the .m4a somewhere you will find it, such as On My iPhone.
• In the converter, tap Pick voice notes or audio files, select the memo (or several), choose MP3 or WAV and tap Convert.
• Tap Share next to the result and send it to Files, Mail, AirDrop or the app that needs it.

Choose WAV if the memo is going into an editor or a transcription tool; choose MP3 if it is going to a car, an email or a website. A ten-minute memo becomes roughly 9 MB as MP3 and somewhere between 50 and 100 MB as WAV depending on the sample rate and channels, which is the main practical difference.

2. Voicemail to MP3

If your carrier supports Visual Voicemail, each message appears in the Phone app's Voicemail tab and can be shared as an audio file. Tap the voicemail, tap the Share button, and choose Save to Files or hand it straight to the converter. The file is .m4a. From there the steps are identical to a Voice Memo.

Two caveats. Not every carrier offers Visual Voicemail, and without it there is no file to share; you would have to play the message on speaker and record it, which is a last resort. And if the voicemail matters for a dispute, convert to WAV, keep the original .m4a as well, and note the date and number before you delete anything from the Phone app, because the file name the app gives you does not preserve the caller.

3. Telegram voice messages to MP3

Telegram voice messages are Opus audio in an .ogg container. iOS can play them inside Telegram and nowhere else: Files shows the file but will not play it, and the Music app will not import it. To convert one, long-press the voice message in Telegram, choose Share or Save to Files, then pick it in the converter the same way as a memo. Because the source is already compressed Opus, MP3 at 128 kbps keeps everything that was there; WAV is only worth it if you are going to edit the file.

If you receive many voice messages from the same person, save a batch to a folder in Files and convert the whole folder in one pass, then share each MP3 as needed.

4. Signal voice messages to MP3

Signal voice messages are .m4a or .ogg depending on the platform and version that recorded them, so a message from an Android contact can arrive in a different format than one recorded on iOS. The converter accepts both. In Signal, long-press the message, tap Save or Share, send it to Files, and convert from there.

Signal users tend to care about where their audio goes, so it is worth repeating the relevant fact: the conversion runs entirely on the phone. You can turn on airplane mode before you convert if you want to see that for yourself.

Choosing MP3 or WAV in one sentence

MP3 if the file is going somewhere to be played or stored; WAV if it is going somewhere to be edited or transcribed. For voice, 128 kbps MP3 is higher than the bitrate of any of the four sources, so you are not losing anything audible; WAV is lossless but ten times the size. If you are unsure, convert to both; it takes a few seconds and you can delete the one you do not use.

The limits, honestly

• The converter cannot get a file out of an app that does not let you share it. Voice Memos, Phone (with Visual Voicemail), Telegram and Signal all do; some corporate voicemail apps do not.
• It does not merge files, trim them or change the volume. For that, convert to WAV and open the result in GarageBand or a desktop editor.
• Converted files are created in the app's cache and handed to the share sheet; save them to Files if you want to keep them, because the cache is not a library.
• The picker shows every file type, not just audio, because iOS has no built-in type for some of these files. That is deliberate, but it means you have to know which file you are looking for.

For the WhatsApp-specific version of this workflow, including where the .opus files hide, see our original guide to converting a WhatsApp voice note to MP3 on iPhone; for the lossless route see converting to WAV for editing and transcription.

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.