Compress WAV audio to MP3 format. Free, private, runs in your browser.
100% private — your files and text never leave your browser. All processing happens locally on your device.
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WAV is an uncompressed audio format that preserves every sample of the original recording — resulting in large file sizes (roughly 10MB per minute of stereo audio). MP3 is a lossy compressed format that reduces file sizes by 90% or more by discarding audio frequencies that most listeners can't perceive. MP3 is the most widely supported audio format in the world.
WAV files are impractically large for sharing, streaming, or storing large music collections. A 3-minute song in WAV is about 30MB; in MP3 at 192kbps, it's about 3.5MB. Converting to MP3 makes audio practical to email, upload to websites, share on social media, and store on portable devices — all while maintaining excellent perceived quality.
Convertful uses FFmpeg compiled to WebAssembly to encode your WAV audio as MP3 at 192kbps — a bitrate that provides excellent quality for music and speech. The entire conversion runs in your browser. On first use, the FFmpeg WASM module (~30MB) is downloaded and cached; subsequent conversions start immediately.
Yes. Your audio files are processed entirely on your device using FFmpeg WASM. No files are uploaded to any server.
MP3 files are typically 90% smaller than WAV while maintaining good audio quality. Ideal for sharing, streaming, and portable devices.
MP3 uses lossy compression, so there's some quality reduction. At 192kbps, most listeners can't tell the difference from the original.
Leave Sample set to Source for the best quality — most listeners never need to change it. Drop to 44.1 kHz if the WAV was recorded at a higher studio rate and you want a smaller universally-compatible MP3. Pick 48 kHz when preparing audio for a video workflow that expects that rate.