How to compress an MP3
- Drop your MP3 files into the box above.
- Choose the bitrate (128 kbps halves a 256 kbps file) and mono or stereo.
- Click Compress and download.
Why GlideConvert?
- Private by design. Your files are converted on your own device by your browser — they are never uploaded to a server. That keeps them private, avoids upload waits and means there is no queue.
- Fast. Images convert in a fraction of a second; video uses your device’s hardware encoder.
- Free. No sign-up, no watermark. 10 images, 5 audio files or one video at a time — Pro lifts the limits and removes ads.
Frequently asked questions
Which bitrate should I choose?
128 kbps stereo is good for music, 64–96 kbps mono is perfect for speech, podcasts and audiobooks. File size is proportional to bitrate: halving it halves the file.
Would another format be smaller?
Yes. At the same quality, M4A (AAC) is about 20–30% smaller and Opus even more, though fewer devices play Opus.
Can I convert several MP3 files at once?
Yes. The free plan handles 5 audio files at a time, and you can download everything as a single ZIP. Pro removes the batch limit, converts files in parallel and supports files up to 4 GB.
Are my files uploaded to a server?
No. GlideConvert runs entirely in your browser: images are processed with the browser’s built-in codecs and WebAssembly, video and audio with hardware-accelerated WebCodecs (or a WebAssembly build of FFmpeg for older formats). Nothing is sent anywhere — you can even disconnect from the internet once the page has loaded.