Free tools for your next audio edit
Open a compatible M4A recording and make a 16-bit PCM WAV in your browser. Choose 44.1 or 48 kHz, keep the decoded mono or stereo layout, and compare the actual export. No account, credits or audio upload. M4A codec support depends on your browser.
Choose a supported M4A and prepare a WAV. No audio upload or account required.
M4A is a container; not every codec or file variant works in every browser. If conversion fails, use the Apple Music, Audacity or FFmpeg methods. This tool does not recover detail lost to AAC, copy tags/artwork, preserve higher bit depth or source codec padding, remove noise, or isolate sound. Input and output must each fit 50 MiB and five minutes; an oversized WAV is rejected rather than cut.
Decode, then write PCM
Use a compatible mono or stereo recording up to five minutes and 50 MiB. Files remain in your browser. A different extension or renamed file is not a substitute for supported encoded audio.
Select the rate needed by your project, then prepare the WAV. The browser decodes at that rate. The output uses 16-bit PCM and retains the decoded channel count; it does not deliberately change gain or trim the recording.
Preview the actual WAV, then download it. Check its duration, channels and bytes. Retain the original M4A; changing the rate clears the current result so the next pass can start from the same source.
Try an original test file
Download the stereo AAC test M4A (49,438 bytes), then select that downloaded file in the converter above. It is a three-second synthesized recording: a 440 Hz tone on the left and an 880 Hz tone on the right, with short edge fades. Start playback at a comfortable volume. This is a format and channel check, not a speech or music quality demonstration.
After conversion, preview the WAV and inspect its stored rate and two channels with the WAV inspector. AAC priming, padding and browser decoding may affect the precise decoded frame count. Success with this file does not establish compatibility with every M4A. The test-file notes and CC0 dedication cover this original synthetic example only.
A container is not one codec
An M4A file commonly stores AAC or Apple Lossless audio, but the extension does not guarantee one encoding or browser behavior. A browser that opens one M4A may reject another file variant. If the metadata or audio cannot be decoded, use the desktop conversion guide for Apple Music, Audacity or FFmpeg instead.
WAV conversion changes the file representation. It is not renaming the file, removing background sound or recovering an original microphone recording from a compressed copy. For AAC, information discarded during the earlier lossy encode does not return when the result becomes a larger PCM file.
Apple Lossless avoids that particular lossy-codec step, but resampling or reducing higher-precision audio to 16-bit PCM can still change stored samples. This tool does not promise a lossless round trip for every M4A. It creates a practical working copy with explicit output settings.
MDN documents that browser audio decoding resamples to the context's rate. The converter checks the actual decoded rate rather than relabeling a WAV header. That working rate is not a report of the source's original sample rate.
Plan the destination
Try a compatible M4A exported from your recording app. Listen for the first and last words after conversion. A file containing speech is not automatically clean dialogue; conversion does not remove a fan, overlapping voice, or captured distortion.
Save the WAV before visiting the next utility. Choose it in the trimmer, channel tool, or another editor. Files are not transferred automatically, and an editor can apply another decode/export step.
At 48 kHz, one minute of stereo PCM16 is 11,520,044 bytes with this basic header. Five minutes can exceed the converter's WAV limit even if the M4A fits. Use the size calculator before exporting a longer working copy in a desktop editor.
Read the actual output
Input and decoded output are limited to five minutes, and both source and WAV must fit 50 MiB. An oversized export fails instead of silently shortening the file. Only mono and stereo are supported; there is no automatic multichannel downmix.
The WAV writes 16-bit PCM at your selected rate, with a basic header. Original tags, album art, container metadata and higher source bit depth are not copied. Samples are rounded to integer PCM; decoded values beyond that range clip during writing. No normalization, limiter or fade is applied. Use the WAV inspector for stored output properties and the loudness meter when levels matter.
Browser codec handling, resampling and AAC priming or padding can affect the decoded frame count and source correspondence. Check the beginning and ending of the actual converted file. The video audio replacement guide explains offsets and sync checks; a format conversion does not automatically align a timeline.
The separate AI uploader has its own supported formats and account/download-credit requirements. This free converter does not run AI separation, detect a speaker, identify a song or publish a result. Save the WAV before leaving the page; neither the original nor the output is stored for a later session.
A few useful answers
Choose an M4A up to 50 MiB and five minutes, select 44.1 or 48 kHz, then prepare the WAV. The browser must support the file’s codec and container. Preview the actual 16-bit PCM export before downloading. Your original M4A is not overwritten.
You can try an exported M4A if its codec is supported by your browser and it fits the mono/stereo, duration and size limits. Files from different settings or applications are not all equivalent. If it cannot be decoded here, use the Apple Music, Audacity or FFmpeg methods in the conversion guide.
No. Converting an AAC source does not restore information discarded by lossy encoding. An Apple Lossless source can also lose precision when exported to 16-bit PCM or resampled. This tool makes a compatible working copy, not a claim of lossless preservation for every source.
A compressed input can be much smaller than uncompressed PCM. At 48 kHz, one minute of stereo 16-bit WAV is 11,520,044 bytes with this basic header. Both source and output must fit 50 MiB; an oversized WAV is rejected rather than shortened. Use the size calculator or a desktop editor for another delivery plan.
The output is a basic 16-bit PCM WAV with decoded channels and the selected rate. Tags, artwork, original bit depth and container metadata are not copied. Browser codec handling, resampling and AAC priming/padding can affect frame count and alignment. Check the actual output before placing it against video or other tracks.
This local converter, preview and WAV download are free without an account or credits. It does not start an AI isolation job. Saturalabs’ separate source-isolation service has its own supported formats, account and download-credit requirements.
After preparing your audio