To convert an iPhone voice memo to MP3, share it from the Voice Memos app as a Rendered .m4a file (Save to Files or AirDrop), then open it in an M4A to MP3 converter and download the result. The conversion takes about a second per minute of audio and does not make the recording sound better or noticeably worse. On SearchSound.cloud, the M4A to MP3 converter runs in your browser, so a private recording never leaves your device.
Below are the exact steps on iPhone and Mac, what we measured when we ran voice recordings through the converter, and how to tell whether you need to convert at all.
Photo by Soundtrap on Unsplash
How do you convert an iPhone voice memo to MP3?
Export the memo as an .m4a file, then convert that file. The iPhone has no "Save as MP3" option, so every route needs a converter.
- Open the recording. In the Voice Memos app, tap the recording, tap the More button (three dots), then tap Share.
- Pick the rendered file. Tap Options and choose Rendered. Apple's guide to sharing a recording describes this as "a single .m4a file with all audio effects and layers mixed in". The other choice, Editable, is meant for opening in Apple software, not for converting.
- Save it somewhere you can reach. Choose Save to Files to keep it on the iPhone, or AirDrop it to a Mac.
- Convert it. Open the M4A to MP3 converter on SearchSound.cloud in Safari or on a computer, choose the .m4a file, keep MP3 selected and tap Convert files.
- Download the MP3. On an iPhone, Safari saves downloads to the Files app, usually in the Downloads folder.
The converter first loads its FFmpeg engine (about 32 MB), so the first conversion on a slow connection takes a little longer. You can select several memos in step 4 and convert them in one go; each one gets its own download button.
Does converting M4A to MP3 lose quality?
A little, in theory, because a standard voice memo is already lossy AAC audio and MP3 encoding removes some detail again. In practice the extra loss is tiny. Apple's own article on converting songs to other formats warns that "some data might be lost" when you convert to a compressed format, and the FFmpeg audio quality guide advises encoding from a lossless source when you have one.
To put a number on it, we took one minute of a public domain spoken sermon from the Internet Archive (a 24-bit WAV), saved it as M4A files at four settings, and converted each one to MP3 with the same FFmpeg WebAssembly build and the same arguments as the converter on SearchSound.cloud. We then compared every file with the original and measured the signal to noise ratio (SNR): how far the waveform has drifted from the source. Higher is closer.
| M4A file we started from | SNR of the M4A | SNR of the MP3 made from it | Extra error from converting |
|---|---|---|---|
| AAC, 64 kbps, mono | 17.8 dB | 17.8 dB | under 0.1 dB |
| AAC, 128 kbps, stereo | 39.2 dB | 39.0 dB | 0.2 dB |
| AAC, 256 kbps, stereo | 46.7 dB | 46.0 dB | 0.7 dB |
| Apple Lossless (ALAC), stereo | identical to source | 50.7 dB | first lossy step |
How to read this table:
- Compare along a row, not down the column. SNR is a rough, non-perceptual measure, and lossy encoders deliberately change parts of the waveform you cannot hear. The useful result is the last column: converting to MP3 moved each file by at most 0.7 dB.
- The MP3 is as good as the memo it came from. It cannot be better: a low-bitrate memo stays a low-bitrate memo.
- Lossless memos lose the most, because they had the most to lose. Converting ALAC to MP3 is a normal lossy encode, the same as making an MP3 from a WAV.
For speech, none of these differences are likely to matter. If the recording is music you care about, keep the original .m4a as well.
Why is my MP3 bigger or smaller than the voice memo?
Because the converter writes a fixed bitrate instead of copying the memo's. With default settings, FFmpeg's MP3 encoder made a 128 kbps file from every stereo input and a 64 kbps file from the mono input, whatever the original bitrate was.
| One minute of audio | M4A size | MP3 size | Change |
|---|---|---|---|
| AAC, 64 kbps, mono | 0.49 MB | 0.48 MB (64 kbps mono) | -3% |
| AAC, 128 kbps, stereo | 0.97 MB | 0.96 MB (128 kbps stereo) | -1% |
| AAC, 256 kbps, stereo | 1.65 MB | 0.96 MB (128 kbps stereo) | -42% |
| Apple Lossless (ALAC), stereo | 2.28 MB | 0.96 MB (128 kbps stereo) | -58% |
To estimate your own memo's bitrate, divide its size by its length: megabytes per minute × 133 ≈ kilobits per second. A 10-minute memo of 5 MB is 0.5 MB per minute, about 67 kbps; the same memo as a stereo MP3 would be about 9.6 MB, while a mono memo stays about the same size.
Conversion was fast: each one-minute file took between 0.8 and 1.2 seconds on our test machine. Phones are slower, so for long recordings a computer is the quicker choice.
What is the difference between Compressed and Lossless voice memos?
Compressed memos are AAC audio and Lossless memos are Apple Lossless (ALAC), and both use the same .m4a extension. Apple describes the setting as "Compressed (for lower-quality, smaller files) or Lossless (for high-quality, larger files)" in its Voice Memos settings guide, and Microsoft's list of file types supported by Windows Media Player notes that .m4a "is often compressed using AAC encoding (lossy), but can also be in Apple Lossless format."
This matters when you share the file. A Lossless memo is several times larger (2.3 MB per minute in our stereo test, against about 1 MB for 128 kbps AAC), and not every device can play it. Converting it to MP3 solves both problems at once.
Do you even need to convert a voice memo?
Often not. A standard Compressed memo plays on most modern devices:
- Android: Google's list of supported media formats includes AAC in .m4a files. Apple Lossless is not on that list, so a Lossless memo may not play without a third-party app.
- Windows: Windows Media Player lists .m4a among its supported file types.
Convert to MP3 when:
- A website or app only accepts MP3, which is common for upload forms, course platforms, voicemail greetings and older podcast tools.
- An older car stereo, MP3 player or USB speaker does not read .m4a files.
- The memo was recorded in Lossless and you want a smaller file or need to send it to an Android phone.
- You want one format for a whole folder of recordings from different apps.
If the memo is too quiet, converting will not fix it; boost it with the volume booster instead (our guide on making an MP3 louder without distortion explains how far you can push it). To cut a long silence at the start or end, use the audio trimmer, which also exports MP3.
How do you convert a voice memo to MP3 on a Mac?
You can use the browser converter, or the Music app that comes with macOS. Apple's article on how to convert an M4A file to MP3 on Mac gives these steps:
- In Music, choose Music > Settings, click Files, then Import Settings.
- Set Import Using to MP3 Encoder and click OK.
- Drag the .m4a file from the Finder into Music and select it.
- Choose File > Convert > Create MP3 Version. The MP3 appears next to the original; choose File > Show in Finder to find it.
The Music route adds the memo to your music library, which some people prefer to avoid. On SearchSound.cloud the conversion happens in a browser tab and nothing is added to your library or sent to a server. For a lot of files on any computer, the free command-line tool FFmpeg does the same job: ffmpeg -i memo.m4a memo.mp3. Our article on whether converting MP3 to WAV improves quality compares the other formats the converter can produce.
FAQ
Can I convert a voice memo to MP3 directly on my iPhone?
Yes. Save the memo to the Files app as a Rendered .m4a, open the M4A to MP3 converter on SearchSound.cloud in Safari, pick the file and download the MP3. No app install is needed, and the recording is processed on the phone instead of being uploaded.
Will the MP3 sound worse than the original voice memo?
Not noticeably. In our test, converting AAC memos to MP3 changed the measured error by 0.7 dB or less, and for speech the difference is very unlikely to be audible. The MP3 cannot sound better than the memo it was made from.
Why can't my Android phone play a voice memo from an iPhone?
The memo was most likely recorded with Audio Quality set to Lossless. Android plays AAC .m4a files, but Apple Lossless is not on Google's list of supported formats. Convert the memo to MP3, or switch the iPhone setting back to Compressed for future recordings.
Can I convert several voice memos to MP3 at once?
Yes. Select all the recordings in Voice Memos, share them as Rendered files to a folder in Files, then select them all in the converter. Each file is converted in turn and gets its own download button.