Audio Converter

Decoding MP3/AAC/Opus and encoding AAC/Opus use the browser's native WebCodecs API. WAV and MP3 encoding work everywhere; the rest need a recent Chrome, Edge, or Safari.

No. All decoding and encoding happens locally in your browser — nothing is sent to a server.

If the source is lossless (WAV or FLAC), yes — MP3 discards detail permanently in exchange for a file roughly a tenth the size. At 192kbps most people cannot hear the difference on ordinary equipment. If the source is already lossy, you lose a little more on top: each re-encode compounds. Where you still have the original, convert from that rather than from an already-compressed file.

For music, 192kbps MP3 is the practical sweet spot and 256kbps is generous. For speech, podcasts and audiobooks, 96-128kbps MP3 is transparent, and Opus at 64kbps is roughly equivalent to MP3 at 128kbps — a genuine halving. Above 256kbps on a lossy codec you are mostly just making the file bigger.

MP3 if you cannot control what will play it — car stereos, gym equipment and older hardware all handle it without question. M4A (AAC) for better quality at the same size across Apple devices and anything modern. Opus if the audience is a browser or a phone and file size matters; it beats the others at nearly every bitrate, but hardware player support is thin.

No. Converting an MP3 to WAV produces a much larger file containing exactly the detail the MP3 encoder already left behind. Nothing is recovered. Convert to WAV when a tool downstream needs raw PCM — for editing or sampling — not in the hope of improving the audio.

No hard limit, but the file has to fit in your browser tab's memory, which is typically 250-500MB. A full-length album as WAV can approach that. If a long recording fails, convert it in sections, or start from a compressed source rather than a lossless one.