Convert M4A to WAV
Turn iPhone voice memos and other M4A recordings into WAV files any editor opens, without uploading them.
- Nothing is uploaded
- Works offline after first use
- Open source
- No sign-up, no watermark. The limit is your device’s memory (phones hold less).
Convert M4A audio and iPhone voice memos to WAV in your browser, ready for Audacity, transcription or editing. It is free, needs no account and adds no watermark, and your files are not uploaded: everything runs in your browser on your device. The limit is your device’s memory, which is smaller on a phone, and after your first run the page works offline.
Your iPhone may take a few seconds to prepare the video first, longer if it's stored in iCloud.
Done
Open the network tab. Your files never appear in it.
Add files and run the tool to see every request this tab makes.
Your files are processed on this device and never sent to a server. Reload the page to clear everything from memory.
M4A is AAC audio in an MP4 container. It is the format of iPhone Voice Memos, GarageBand and Music exports, many Android recorders and WhatsApp audio. It is small and sounds good, but a lot of tools that work on recordings want WAV: transcription and captioning services, speech analysis, older editors, hardware samplers, and research or legal workflows that must keep an unaltered, uncompressed copy.
Audacity is the usual stumbling block. It opens WAV out of the box but needs a separate codec library before it can import M4A, and installing that is where many people give up. Converting the memo to WAV first sidesteps it entirely.
This page decodes the M4A with your browser’s own AAC decoder and writes a 16-bit, 44.1 kHz PCM WAV. Recordings made at 48 kHz are resampled to 44.1 kHz, with no audible change. A mono voice memo stays mono and takes about 5 MB per minute. A stereo recording takes about 10 MB per minute, or half that if you choose mono.
Recordings of interviews, lectures, therapy or medical appointments, and notes to yourself are exactly what should not be handed to an upload site. Here the memo is read from your disk and the WAV is written back to it, and the audio never goes anywhere else.
How it works
- Drop one or more M4A files, or tap to pick them. On an iPhone, save the memo to Files from Voice Memos first, then choose it here.
- WAV is already chosen. Pick mono for a stereo recording of a single voice.
- Convert. The WAV downloads; several files come as a zip.
In your browser, not on a server
Your browser decodes the sound track with the same audio decoders it uses to play media on any website (AAC for MP4, MOV and M4A; Opus or Vorbis for WebM; FLAC, WAV and MP3). The samples are resampled to 44.1 kHz and handed to LAME, the reference MP3 encoder, compiled to WebAssembly and served by this site. WAV files are written directly by a few lines of code in the page. Everything happens in memory in your tab.
Compared with upload-based tools: Online converters upload the whole video just to keep its sound, cap free files at a few hundred megabytes, and make you wait in a queue. Home videos, lectures and voice memos are personal. Here the file never leaves your device, so a 1 GB video converts as fast as your computer can read it, and the limit is your device’s memory (phones hold less).
Verify it yourself. Give the page a short while after your first run to save itself for offline use, then turn off Wi-Fi or switch to airplane mode and run the tool again. Or open your browser's developer tools (F12, or Cmd-Option-I on a Mac), pick the Network tab, and watch it while you convert. The panel above does the same count for you.
Questions
How do I get a voice memo off my iPhone?
In Voice Memos, tap the recording, tap the three dots, then Save to Files. Open this page in Safari, tap the drop zone, and pick the memo from Files. The WAV is saved to Downloads in Files.
Will the WAV sound better than the M4A?
It sounds the same. The AAC audio is decoded once and stored uncompressed, which stops any further loss while you edit, but it cannot restore detail AAC removed.
Can I convert M4B audiobooks or .m4p songs?
M4B audiobooks without DRM convert like any M4A, though one long chapter file makes a very large WAV. Protected .m4p songs from the old iTunes Store use FairPlay DRM, which browsers cannot decode.
Is the file uploaded anywhere?
No. There is no server in this process. The page is a static file and the work is done by code running inside your browser tab. Give the page a short while after your first run to save itself for offline use; then you can turn off Wi-Fi and it still works.
More video and audio tools
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Change video speed
Make a video faster or slower, with sound that stays at the right pitch. Done on this device, never uploaded.
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Combine clips into a single video, in the order you choose. Done on this device, never uploaded.
Other conversions
Guides
- How to convert a video to MP3This is different from muting a video: you want the sound saved as its own file. Most devices have no built-in way to do that.
- Is CloudConvert safe?For most files, yes: it is an established, certified service. The real question is whether a given file should leave your computer at all.
- Is FreeConvert safe?FreeConvert is a legitimate service with a clear deletion policy. Whether it is safe for a particular file depends on whether that file should be uploaded anywhere.
- Is Convertio safe?Convertio is a well-known converter with a published deletion policy. For private files, the safer choice is a converter that never receives them.
- Is Zamzar safe?Zamzar is one of the oldest online converters. Its storage window is longer than most, which is the detail worth knowing.