How to do it, step by step
- Select the audio.
- Keep the MP3 format and choose 128k (or less) in Bitrate.
- If it is voice, choose Mono under Channels and 22.05 kHz under Sample rate.
- Convert and compare the size of the result with the original.
When this is useful
Attach recordings to emails
A one-hour meeting in WAV weighs hundreds of MB; as 128k mono MP3 it gets much smaller.
Send through apps with a size limit
Reduce before sending so as not to hit the file limit.
Tips for a good result
- The biggest gain comes from converting WAV (uncompressed) to MP3.
- Mono at 128k reduces the size a lot and is enough for speech.
- For music, avoid going below 192k.
What this tool does not do
- If the audio is already a low-bitrate MP3, the gain is small and the quality drops.
- The reduction is lossy: you cannot recover the quality afterwards.
- The app converts the format; there is no automatic reduction to a desired final size.
Frequently asked questions
- Which setting gives the smallest file?
- MP3 at 128k, mono and 22.05 kHz are the app’s most economical options, suitable for voice.
- Can I reduce a video too?
- For videos, use WebFaz Video Compressor.
More Audio Converter tools
Text written by Marcelo Amantino · updated October 18, 2026 · who we are