MP3 Compressor — online
Compress MP3 audio files online for free. Reduce file size.
Click or drag a .MP3 file here
How to use MP3 Compressor
Click the upload button to select your MP3 file
Locate the blue 'Upload MP3' button in the center of the page. Click it to open your device's file browser. Navigate to your MP3 file and select it. The file will immediately begin uploading to the compression tool.
Adjust the compression quality slider if needed
Once uploaded, you'll see the Quality slider on the right panel (default set to 192 kbps). Drag left to reduce file size more aggressively (128 kbps for maximum compression) or keep default for balanced quality. Preview the bitrate reduction percentage displayed below the slider.
Click the Compress button to process your audio
Press the green 'Compress Now' button below the quality settings. A progress bar will appear showing compression status. Processing typically completes in 10-30 seconds depending on file size.
Download your compressed MP3 file
Once complete, click the 'Download Compressed MP3' button to save the file to your device. Your original file remains unchanged. The new file size is displayed in the success message.