How to convert MP3 to WAV on a Mac
By Himanshu Ranjan · Updated 8 November 2026
Select the MP3 files in Finder, open FileDial, and run Convert › Convert to WAV. A WAV copy appears beside each original and nothing leaves your Mac. The WAV will be much larger and will not sound better than the MP3, but editing software and some hardware require it.
Why anyone converts MP3 to WAV
WAV is an uncompressed container that editors, samplers, broadcast chains and some hardware expect. Converting an MP3 to WAV does not restore detail the MP3 already discarded. It only unpacks the audio into a format that is easy to edit without further lossy generations.
Expect a large jump in size. Uncompressed stereo audio at CD settings runs around 10 MB per minute (the AIFF article gives that figure for 44.1 kHz, 16-bit stereo, and WAV PCM is the same size), compared with a small fraction of that for MP3.
Convert with FileDial
- Select one or more .mp3 files in Finder.
- Hold the right Option key to open the dial.
- Choose Convert › Convert to WAV and release.
- Open the new .wav beside each MP3. Undo on the result card removes it.
Terminal alternative: afconvert
macOS ships a command-line converter called afconvert. To make a 16-bit WAV from an MP3, run: afconvert -f WAVE -d LEI16 input.mp3 output.wav. The -f option sets the file format and -d the data format, where LEI16 means little-endian 16-bit integer samples. Run afconvert -h to see the options on your Mac.
That is quick for one file and fiddly for fifty, since you need a loop or script. FileDial does the batch from a Finder selection.
The Music app route
Music can also create WAV versions: in Music › Settings › Files › Import Settings set Import Using to WAV Encoder, then use File › Convert › Create WAV Version. Apple says converting compressed audio to an uncompressed format should not reduce sound quality, though it cannot add quality either. The songs must live in your Music library.
WAV or AIFF
Both are uncompressed PCM. WAV is the Windows-origin format, published by IBM and Microsoft in 1991, and AIFF is Apple's, dating from 1988. On a Mac either works in most apps. Choose WAV when the destination is Windows software or hardware, and note that classic WAV files cap just under 4 GiB. FileDial also offers Convert › Convert to AIFF.
Match the sample rate and bit depth to the job
Bit depth is the number of bits stored for each sample, and the sample rate is how often the signal is measured. The sample rate limits the frequency response, while the bit depth does not. CD audio uses 16 bits per sample, which gives 65,536 possible amplitude values.
For a conversion from MP3 there is no benefit to chasing higher numbers, because the source never had more detail than it has. If a project needs a specific format, follow the project spec, and use the converter that exposes that setting. FileDial's Convert › Convert to WAV is the quick path for ordinary editing and compatibility use.
Edit first, convert last, or the other way around
A good rule is to keep one lossy generation only. If you plan to trim, fade or fix loudness, you can do it on the WAV so the edit does not add another round of MP3 compression, then export the final MP3 once. Edit › Trim…, Edit › Fade in & out and Edit › Normalize loudness all write new copies beside the file. See the trim guide for the cutting steps.
If you are just handing a file to someone who insists on WAV, convert once and send it.
Troubleshooting
If a WAV will not open in a very old program, the likely cause is the size limit: WAV files are capped just under 4 GiB, around 6.8 hours of CD-quality stereo, so a very long recording needs to be split into parts first. If the audio sounds identical to the MP3, that is expected. If a name has a double extension like song.mp3.wav, rename it with Rename › Replace text in names…, which leaves extensions alone.
What to check before and after
Before converting, ask whether the destination really needs WAV. Many editors open MP3 directly, and converting only adds disk use. After converting, compare the duration of the MP3 and the WAV in a player: they should match. If you plan to send the file to a broadcaster or a mastering service, ask what sample rate and bit depth they want, since requirements differ and a plain conversion will not choose them for you.
In Terminal, afinfo prints the format, sample rate and duration of an audio file, which is a quick way to verify a result before you hand it over.
Keeping it private
A web converter would receive your tracks, which may be unreleased mixes or client work. FileDial runs every tool on your Mac and never uploads a file, and all tools work with Wi-Fi off.
Questions
Does converting MP3 to WAV improve the sound?
No. An MP3 has already lost detail through lossy compression, and WAV just stores what remains without further compression. The benefit is compatibility and safer editing, not better quality. The file will be many times larger. The sound is identical to the MP3 apart from the format, so the benefit is editing safety and compatibility.
Why is the WAV so much bigger than the MP3?
WAV usually stores uncompressed PCM, so every sample is kept in full. MP3 compresses heavily. One minute of CD-quality stereo takes about 10 MB uncompressed, so a typical song becomes tens of megabytes. Roughly speaking, uncompressed CD-quality stereo takes about 10 MB per minute, while a typical MP3 is a small fraction of that.
Can I batch convert MP3 to WAV on a Mac?
Yes. Select every file in Finder and run Convert › Convert to WAV once. FileDial makes a WAV beside each MP3 and keeps the originals. In Terminal you can do the same with afconvert in a shell loop. Mixed batches are fine because every file is decoded and written as its own WAV, and the MP3 originals are left in place.
Is the afconvert command safe to use?
Yes, it is Apple's own audio conversion tool and writes a new file to the destination you name. Be careful to give it a different output name than the input so you do not overwrite your source. Still, double-check the destination file name, because afconvert will happily overwrite an existing file that has the same output name.