Free converter · Lossy re-encode
Convert MP3 to WAV
Short answer
Drop your MP3 file into the converter below and download the WAV file. It runs in your browser with FFmpeg, for files up to 100 MB; nothing is uploaded. The file is re-encoded to 16-bit PCM audio in WAV. WAV keeps every sample of what it receives, but it cannot restore what MP3 compression already removed, so the result sounds the same and is larger.
Maximum file size: 100 MB. The first conversion loads a ~30 MB converter engine, once per visit. Nothing is uploaded - conversion runs on your device.
MP3 is already lossy; expanding to WAV does not restore what MP3 discarded. · Lossy re-encode · Browser-side via FFmpeg WASM - nothing uploaded.
Key takeaways
- The 242 KB MP3 file became a 1.92 MB WAV file (+695%), about 1536 kbps for the 10 second clip.
- The result holds: Audio: pcm_s16le 48000 Hz 2 ch.
- In your browser the same conversion of a 3 second clip took 0.04 seconds on the single-thread engine; natively, the 10 second clip took 0.09 seconds.
- Next to it: MP3 to AAC (-32.1%), MP3 to FLAC (+559%), MP3 to M4A (-32.3%).
Measured: MP3 to WAV
The converter's own ffmpeg arguments, run on a 10 second 1920 × 1080 excerpt of Big Buck Bunny (an animated film, not camera footage) saved in MP3. The browser column is the same arguments on the single-thread WebAssembly core with a 3 second excerpt, in a headless run; your device will differ. Results describe this clip and these encoders.
| Check | Result |
|---|---|
| Mode | Audio re-encoded |
| Input | MP3, 242 KB |
| Output | WAV, 1.92 MB (+695%) |
| Output streams | Audio: pcm_s16le 48000 Hz 2 ch |
| Time, native, 10 s clip | 0.09 s |
| Time, browser engine, 3 s clip | 0.04 s |
A re-encode decodes and encodes every frame or sample, so the time grows with the length of the file.
MP3 vs WAV
| MP3 | WAV | |
|---|---|---|
| Full name | MPEG-1 Audio Layer III | Waveform Audio File Format |
| What is inside | MP3 audio | Uncompressed PCM audio |
| Compression | Lossy | Uncompressed |
| Best for | Music and podcasts that must play on every device | Editing and mastering, where every sample matters; very large files |
What you get
16-bit PCM audio in WAV. MP3 is already lossy; expanding to WAV does not restore what MP3 discarded.
Planning a bigger file
These are estimates scaled up from the 10 second clip. Real files differ with content, resolution and bitrate, so treat them as an order of magnitude, not a promise.
| Length of the video or recording | Input size (like ours) | WAV size | Time in your browser |
|---|---|---|---|
| 1 minute | 1.45 MB | 11.52 MB | 1 seconds |
| 10 minutes | 14.48 MB | 115.21 MB | 8 seconds |
| 1 hour | 86.91 MB | 691.24 MB | 46 seconds |
An MP3 file of this kind reaches the 100 MB limit of the converter after about 72 minutes; converting it would take roughly 55 seconds on the single-thread engine, and the WAV would be about 834.02 MB.
MP3 and WAV next to their neighbors
The same clip through other conversions with the same source or the same target.
| Conversion | How | Size change | Time (native) |
|---|---|---|---|
| MP3 to WAV | Re-encode | +695% | 0.09 s |
| MP3 to AAC | Re-encode | -32.1% | 0.30 s |
| MP3 to FLAC | Re-encode | +559% | 0.11 s |
| MP3 to M4A | Re-encode | -32.3% | 0.29 s |
| MP3 to OGG | Re-encode | -50.7% | 0.23 s |
| MP3 to Opus | Re-encode | -51.7% | 0.10 s |
| AAC to WAV | Re-encode | +686% | 0.09 s |
Choosing WAV
WAV: Waveform Audio File Format. Editing and mastering, where every sample matters; very large files. MP3: MPEG-1 Audio Layer III. Music and podcasts that must play on every device.
- Keep your original: a re-encode is a copy of a copy.
- If the destination states the format it accepts, use that and nothing else.
Questions people ask
Is this MP3 to WAV converter free and private?
Yes. It is free, needs no account and runs entirely in your browser, so the file never leaves your device.
Will converting MP3 to WAV reduce quality?
WAV adds no loss of its own, but quality cannot be better than the MP3 you start from.
Is there a file size limit?
Files up to 100 MB. The first conversion downloads a converter engine of about 30 MB once per visit; larger files are better handled by a desktop app such as HandBrake or FFmpeg.
How do I convert MP3 to WAV?
Choose the file in the converter above and download the WAV. It runs in your browser with no upload.
Will converting MP3 to WAV reduce quality?
WAV adds no loss of its own. Keep the original file.
Why did the file size change by +695%?
The target codec and settings decide the size. This 10 second clip came out at 1.92 MB, about 1536 kbps.
How long does it take?
A 3 second clip took 0.04 seconds in the browser engine in our test; time grows with the length of the file.
How long will an MP3 file of 100 MB take?
At the speed we measured in the browser engine, about 55 seconds for a file like our clip. Your device and the content will change it.
Is my file uploaded?
No. The conversion runs in your browser.
Is there a size limit?
Files up to 100 MB. The first conversion downloads a converter engine of about 30 MB once per visit.
More converters
Sources and how we checked
- MDN: Media container formats
- MDN: Web audio codec guide
- MDN: Image file type and format guide
- FFmpeg documentation: stream copy
- FFmpeg Documentation: ffmpeg (stream selection, -map, -c copy) (read 2026-10-09)
- MDN: Web audio codec guide (read 2026-10-09)
- Blender Foundation: Big Buck Bunny (CC BY 3.0), the clip used for the measurements (read 2026-10-09)
Reviewed October 8, 2026. What the converter writes was measured with ffprobe on the same FFmpeg build your browser downloads; format descriptions follow MDN's media guides.