Audio
WAV to MP3, without uploading the file
WAV files are enormous because nothing is compressed. Converting to MP3 typically cuts the size by ninety percent, and at a high bitrate almost nobody can hear the difference.
Files are processed on your device · nothing is uploaded, stored or logged
How it works
Pick your file. The browser reads it straight from disk. There is no upload progress bar, because there is no upload.
The encoder loads once. A WebAssembly build of FFmpeg, around 30 MB, downloads the first time you use the site and stays cached afterwards.
Your processor does the work. Everything happens in this tab, at roughly half of real time on a modern laptop.
Save the result. The finished file is assembled in memory and handed to your downloads folder.
Why WAV files are so large
WAV stores audio exactly as it was captured, sample by sample, with no compression at all. A minute of CD-quality stereo runs about 10 MB, so an hour-long recording lands near 600 MB.
That is exactly what you want while editing, because every pass through a lossy format loses a little more. It is exactly what you do not want when the file has to be emailed, uploaded or carried on a phone.
MP3 at 320 kbps brings the same hour down to roughly 140 MB. At 192 kbps it is closer to 85 MB, and for spoken word 128 kbps is genuinely enough.
Convert last, not first
If the recording still has editing ahead of it, keep the WAV and convert at the end. Each lossy encode discards detail permanently, and stacking them produces the thin, swirly sound people describe as over-compressed. One conversion at the finish line costs almost nothing.
Common questions
Will I hear the difference?
At 320 kbps, almost certainly not, on almost any equipment. At 128 kbps you may notice it in cymbals and reverb tails.
Can I convert back to WAV later?
You can, but the detail removed during compression does not come back. The result is a large file of lossy audio.
Which bitrate for a podcast?
128 kbps is plenty for speech and keeps episodes small enough to stream comfortably.
Do my files get uploaded?
No. The conversion runs on your own machine, inside this tab.