Compress audio. For free.
Shrink a heavy MP3, WAV or FLAC so it's easy to send and store, high-bitrate and lossless files often drop a lot. Keeps the same format, no watermark, no signup, and if it's already small we hand back your original, never a bigger file.
Smart
Keeps the smaller of the two
Private
Encrypted upload, our own engine
Temporary
Deleted after 1 hour
How it works
- 01
Add your audio
Drop in an MP3, WAV, AAC, FLAC, OGG or M4A, or click to browse. Uploaded privately over TLS.
- 02
We compress it
We re-encode at an efficient bitrate for a big size cut while keeping it clear for listening.
- 03
Download the smaller file
See exactly how much you saved, then grab the lighter audio. Everything is deleted after 1 hour.
Worked example
A 320 kbps song made 60 percent smaller
We compressed a 3 minute, 320 kbps MP3 of 7,202,524 bytes. It came back at 128 kbps and 2,881,035 bytes, the same 3 minutes, in 762 milliseconds. Then we ran that 128 kbps result through again: it came back at exactly 2,881,035 bytes, the original untouched, because there was nothing more to save.
Measured on 19 October 2026 by running the conversion engine this page uses on our own test files.
What it does not do
It does not shrink an MP3 that is already at 128 kbps or lower: that file comes back unchanged.
Common questions
How much smaller will it get?+
It depends on the source, high-bitrate MP3s and especially WAV/FLAC often shrink dramatically. If a file is already low-bitrate we tell you and hand back the original untouched, so you never end up with a bigger file.
Will it keep the same format?+
Yes. An MP3 stays an MP3, a WAV stays a WAV. We just re-encode it smaller. To change format (e.g. WAV → MP3), use our audio converters instead.
Is my audio private?+
Yes. It's uploaded over an encrypted connection to our private storage (Supabase, named in our privacy policy), compressed on our own server, never by an outside conversion service, and the upload and result are deleted after 1 hour.
Will it ruin the quality?+
We use a balanced bitrate that stays clear for voice, music and podcasts at everyday listening. For the biggest savings, very high-bitrate files are brought down to a sensible level.
Is there a limit?+
No watermark and no signup. Free covers 10 server conversions a day, up to 100 MB a file. Pro removes the daily limit and raises the file limit to 2 GB.
How do I compress an MP3 file?+
Upload it and download the result. A high bitrate MP3 is re-encoded at 128 kbps, which in our test took a 320 kbps song from 7,202,524 to 2,881,035 bytes.
How much can I reduce the file size of an MP3?+
It depends on where it starts. From 320 kbps to 128 kbps the file is about 60 percent smaller. An MP3 already at 128 kbps or lower cannot be made meaningfully smaller this way, so you get it back unchanged.
Can I compress an MP3 below 16 MB?+
At 128 kbps a minute of audio takes about 1 MB, so anything up to about 16 minutes comes in under 16 MB. Our 3 minute test song came back at 2,881,035 bytes.
Need more than a conversion?
Send your audio or video to TranscriptAI to generate a transcript, summary, structured notes, flashcards, quiz questions or action items: automatically.