Compress audio to a smaller MP3
Reduce audio file size for easy sharing.
To compress audio, upload a file, pick a target bitrate of 64, 96 or 128 kbps and download a smaller MP3. The audio compressor re-encodes the whole recording as MP3 at the bitrate you choose, so the file size follows the bitrate and length rather than the original format. Lower bitrates make smaller files but lose more detail. The tool shrinks file size; it does not do dynamic range compression, which evens out loud and quiet parts.
How to compress an audio file
Choose an audio file up to 50 MiB in MP3, WAV, FLAC, OGG, AAC or M4A format, set the target bitrate and submit. The result is always an MP3 whose name ends in -compressed. The page shows the file sizes so you can compare them with the original before you delete anything.
Choosing 64, 96 or 128 kbps
At 64 kbps speech such as voice memos, lectures and podcasts stays clear, while music sounds thin. At 96 kbps (the default) most spoken audio is comfortable and music is acceptable. At 128 kbps music is a reasonable compromise between size and quality. As a rough guide, one minute of audio takes about 0.5 MB at 64 kbps and 1 MB at 128 kbps.
When the file will not get smaller
Compression is a re-encode, not a guarantee. A file that is already an MP3 at 64 kbps will not shrink at 96 or 128 kbps and may grow. Large WAV and FLAC files usually shrink dramatically, because they hold uncompressed or lossless audio. Re-encoding a lossy file also adds a second round of quality loss, so keep your original.
Compression versus other fixes
If you only need a different format, use the Audio Converter, which offers higher bitrates. If a recording is long, the Trim Audio tool can remove silence at the start or end. To make quiet audio louder instead, use the Audio Normalizer.
Frequently asked questions
How do I compress an MP3 file?
Upload the MP3, choose 64, 96 or 128 kbps and download the result. If your file is already at or below the bitrate you pick, the output may be about the same size, so pick a lower setting.
What format is the compressed audio?
Always MP3, whatever format you upload. The output file keeps your original name with -compressed added at the end. If you need another format afterwards, run the result through the Audio Converter.
Does compressing audio lower the quality?
Yes. The tool re-encodes the audio at a lower bitrate, which discards detail to save space. 128 kbps is the gentlest option here. Keep the original file if you may need full quality later.
How small can I make a WAV file?
A WAV usually shrinks by around ten times at 128 kbps, because WAV is uncompressed. Exact results depend on the recording. The page shows the original and new sizes so you can check the saving.
What is the maximum audio file size?
Each upload can be up to 50 MiB, one file at a time. Processing also stops if it runs longer than three minutes, so split very long recordings with Trim Audio and compress the parts.
Related tools
Audio Converter
Convert between MP3, WAV, FLAC and more.
Use tool →Trim Audio
Cut an audio clip down to a specific start and duration.
Use tool →Merge Audio
Combine multiple audio clips into one, in order.
Use tool →Audio Speed Changer
Speed up or slow down an audio clip.
Use tool →Audio Normalizer
Even out and boost the loudness of an audio clip.
Use tool →