AUDIO CONVERTER
MP3 Compressor
Make an MP3 smaller for email, messaging, or a strict upload limit by re-encoding it at a lower bitrate in your browser.
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Try a sample file and preview the converted MP3.
Compress an MP3 in three steps
- Choose one or more MP3 files, or try the included sample.
- Pick a target bitrate and press Compress MP3. Keep this tab open while it works.
- Listen to the preview and save individual files or download the batch as a ZIP.
Why compress an MP3
Email attachments, messaging apps, and upload forms often refuse files over a few megabytes. A speech recording at 320 kbps is much larger than it needs to be. Re-encoding at 96 or 128 kbps keeps speech clear and cuts the file to a fraction of its size.
How it works
The converter decodes the MP3 to raw audio and encodes a new MP3 at your chosen bitrate. Duration, sample rate, and channels are preserved. The work happens in your browser, so a private interview does not leave your device.
Choosing a bitrate
Use 64 kbps for voice when size is critical, 96 or 128 kbps for normal speech, and 192 kbps for music. Any lower bitrate than the original saves space, and a higher one only makes the file bigger. Listen to the result before sending it.
Tips
Compress only the final version of a file, because each re-encoding costs a little quality. If the recording has long silent stretches, the silence remover can shorten it first and save more space than lowering the bitrate. Tags and cover art are best re-added with the MP3 tag editor afterwards.
Frequently asked questions
How much smaller will my MP3 get?
File size is proportional to bitrate. Going from 320 to 128 kbps cuts the file to 40 percent of its size, and 64 kbps cuts it to 20 percent.
Which bitrate should I pick to compress an MP3?
Use 96 or 128 kbps for speech and 64 kbps for a spoken-word recording that must be tiny. Keep 192 kbps or more for music.
Does compressing an MP3 reduce the quality?
Yes. It is a second lossy encoding, so keep the original. Choosing a bitrate higher than the original does not restore detail and makes the file bigger.
All processing runs locally in your browser memory via WebAssembly and Web Audio. Files never leave your device. Built-in peak limiting prevents audio clipping.
AudioClover Engineering · Updated October 2026KEEP IN THE LOOP
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