filetity

WAV -> MP3 · Local tool

WAV to MP3

Convert a WAV recording to MP3, around a tenth of the size.

Last updated

How do I convert WAV to MP3 without uploading it?

Drop the WAV onto filetity's converter and it becomes an MP3 inside the browser tab, with nothing uploaded and no size cap beyond your own device. The saving is large because WAV stores raw uncompressed samples: a stereo CD quality WAV runs at about 1,411 kbps against 128 to 192 kbps for a good MP3, so a 50 MB recording usually lands near 5 MB. There is no decoding step on the way in, which is why it is fast even on long files. One thing the page tells you before you start rather than afterwards: MP3 supports only six sample rates and none above 48 kHz, so a 96 kHz studio recording is brought down to 48 kHz, and that is a limit of the format rather than of the tool.

  1. 01 / Your device

    the file stays here

  2. 02 / Browser memory

    the work runs locally

  3. 03 / Back to you

    saved on this device

When you would use this

Situations, not settings.

A voice recorder or field recorder full of WAV files
Handheld recorders write WAV by default. Converting drops each file to roughly a tenth of the size before it goes anywhere near a phone or an upload form.
An upload form that will not take the file
Podcast hosts and submission forms usually cap at a size a WAV blows past in a couple of minutes. An MP3 of the same recording usually walks straight in.
Exports from editing software
A DAW hands you a WAV because that is the right thing to master from. It is the wrong thing to send anybody, and this is the last step before you do.

How it works / no cloud

A conversion engine, not an upload form.

A WAV holds raw uncompressed samples, so there is nothing to decode: filetity reads the samples straight out and hands them to an MP3 encoder running in your browser. That is why this conversion is quick even on a large file, and why the size drops so far, since the input was never compressed in the first place.

  • Offline ready
  • Installable app
  • No file limit queue

Straight answers

No accordion. Nothing hidden.

Is it free?
Yes, with no watermark and no page limit.
Does it need an account?
No. There is no account system.
Is my file processed on my device?
Yes. The file is read by your browser and never uploaded. There is no server to send it to.
What formats are supported?
WAV in, at any sample rate and channel count. MP3 out at up to 320 kbps, or M4A and OGG if you prefer.
What are the limits?
MP3 supports six sample rates and nothing above 48 kHz, so a 96 kHz studio file is brought down to 48 kHz and the page says so before you start.
Does it work on mobile?
Yes, on any modern mobile browser. Large files are limited by the memory the phone gives the browser.
Does it work offline?
Yes, once the page has loaded. The tool keeps working with no network connection.
How much smaller will the MP3 be?
Usually about a tenth. A stereo CD quality WAV runs at roughly 1,411 kbps, and a good MP3 sits at 128 to 192 kbps, so a 50 MB recording lands somewhere near 5 MB. The exact number is shown before you press anything, and again afterwards.
What happens to a 96 kHz studio recording?
It is brought down to 48 kHz, because the MP3 format supports only six sample rates and 48 kHz is the highest of them. That is a limitation of MP3 itself rather than of this tool, and the page tells you before you convert instead of quietly changing your file.
Can I get the WAV back afterwards?
You can produce a WAV from the MP3, but it will not be the file you started with. MP3 discards information permanently, and decoding it back to WAV restores the size without restoring what was thrown away. Keep the original WAV if you may need it.
Which bitrate should I pick?
For speech and podcasts the smallest setting is usually indistinguishable and gives you a much smaller file. For music, the middle setting is the safe default and the highest is worth it only if you know the material and the listening setup justify it. The tool never asks for more than the source actually contains.
Does converting change the length or the channels?
The length is preserved exactly. Channels are preserved up to stereo; a recording with more than two channels is mixed down, because MP3 as written here handles mono and stereo. The page states the channel count it is going to write before it runs.

Keep working locally

3 available · more coming