MP3 Compressor

Yes. This page accepts MP3 audio files only and saves the result as MP3. Files must pass extension, MIME type, and audio-header checks. For WAV-to-MP3 compression or sources in M4A, FLAC, OGG, or AAC format, use the general Audio Compressor.

Light is 192 kbps, Medium is 128 kbps, Heavy is 96 kbps, and Extreme is 64 kbps. Medium is selected initially. Lower bitrates usually use less space but can reduce clarity, especially in music with complex sounds.

No. The tool re-encodes audio using lossy MP3 compression, and each encoding pass can discard audio detail. Light uses a higher bitrate than the other levels, but it does not make the conversion lossless or improve a poor source recording.

No. A file already encoded at a low bitrate can grow if you choose a higher bitrate. Short tracks, embedded artwork, and metadata also affect the result. This tool compares actual sizes rather than promising a fixed percentage reduction. You can still download a valid result if it is larger.

Compatible text metadata and embedded JPEG or PNG album artwork can be copied into the new MP3. Unsupported fields or covers may be omitted. Keeping tags and artwork can make a compressed file larger than the audio bitrate alone suggests.

Changing a level creates a new attempt from the original uploaded MP3, not from an earlier compressed result. Your last successful download stays available until a replacement succeeds, including when an attempt is cancelled or fails.

You can select up to 10 MP3 files on desktop and 5 on mobile. The combined input limits are 200 MB and 100 MB, respectively. Output size, saved results, ZIP limits, and device memory also apply.

No. You can compress MP3 files online for free without installing a desktop app or creating an account. Audio processing runs locally in your browser; your MP3 files are not uploaded to a processing server. The FFmpeg engine downloads its code when needed. Keep the page open while it works and save your results before leaving.