Audio Compressor
Compress audio files by adjusting the bitrate. Output as MP3 for maximum compatibility.
Drop an audio file here or click to browse
Supports MP3, WAV, OGG, AAC, FLAC, M4A
Shrink audio files without the hassle
The Audio Compressor reduces the file size of your music, voice recordings, and other audio by re-encoding it as MP3 at a bitrate you choose. Lower bitrates throw away more audio data, producing dramatically smaller files, while higher bitrates keep more detail. This is the trade-off at the heart of every lossy audio format, and this tool puts that dial directly in your hands.
It is useful any time a file is too large to share: email attachments that bounce because they exceed a size limit, voice memos you want to upload to a messaging app, podcast drafts, or a music library you want to fit on a small device. Because the output is always MP3, the result plays on virtually every phone, browser, car stereo, and media player without any extra software.
Everything happens inside your web browser using FFmpeg compiled to WebAssembly. Your audio file is never uploaded to a server; it is read, re-encoded, and offered back to you for download entirely on your own computer. That makes it suitable for private recordings you would not want to send to a third party.
How to use the Audio Compressor
Drag an audio file onto the upload box, or click it to browse and pick a file. The tool accepts common formats including MP3, WAV, OGG, AAC, FLAC, and M4A, and it shows the original file size once a file is loaded.
Choose an output bitrate. 64 kbps gives the smallest files and is fine for spoken-word audio; 128 kbps is a sensible default for most uses; and 192, 256, or 320 kbps keep progressively more quality at the cost of size. Then click Compress Audio. The first run downloads the FFmpeg engine, so it may take a few extra seconds; later runs are faster.
When processing finishes you will see the original and compressed sizes side by side, along with how much space you saved. Preview the result in the built-in player, then click Download Compressed Audio to save the MP3 to your device.
Tips for the best results
Compression is lossy, so re-compressing a file that was already heavily compressed can audibly degrade it. When possible, start from the highest-quality source you have, such as a WAV or FLAC original. For spoken content like interviews and lectures, 64 to 96 kbps usually sounds fine and saves the most space; for music, 192 kbps is a good balance of size and fidelity.
Remember that picking a bitrate higher than the source recording will not add quality back, it will only make the file larger. Large files take longer to process because all the work runs locally on your machine, so very long recordings on an older device may need a little patience.