Convert MP3 to FLAC online

Your MP3 file is converted to FLAC right here in your browser, using FFmpeg compiled to WebAssembly. Nothing is uploaded to us, the audio never leaves your device. Quality is preserved and the download is ready in seconds.

What is an MP3 file?

MP3 (MPEG-1 Audio Layer III) is the format that made digital music portable in the late 1990s, and it remains the most universally supported audio format ever made. It compresses audio by discarding detail the ear is least likely to miss, at bitrates typically between 128 and 320 kbps.

Almost everything plays MP3: every phone, car stereo, browser, WhatsApp attachment and email client. It is the safe default when you don't know what device the other person has.

Why FLAC?

FLAC (Free Lossless Audio Codec) compresses audio the way ZIP compresses files: the data gets smaller (typically 50 to 60% of WAV size) but decodes back to exactly the original samples. Nothing is lost, ever.

Convert to FLAC to archive: you keep bit-perfect quality at roughly half the size of WAV, with full metadata and checksum support built in. It is the right long-term home for irreplaceable recordings. MP3 is showing its age: newer lossy formats like AAC and Opus sound better at the same file size, and every re-encode of an MP3 loses a little more detail.

Frequently asked questions

Will converting MP3 to FLAC lose quality?

Honest answer: quality stays exactly where it is, no better, no worse. FLAC is lossless, but it cannot restore detail your MP3 already discarded when it was first encoded. What you gain is safety: the FLAC copy can be edited and re-exported repeatedly without any further loss, which is exactly why editors ask for it.

Is it free?

Yes, completely, with no account and no watermark. The conversion runs on your own device, so it costs us nothing to let you use it. The only limit is file size: up to 50 MB, which is what a browser can hold in memory comfortably.

Do I need to install anything, or upload my file?

Neither. It runs entirely in your browser using FFmpeg compiled to WebAssembly. Your audio is never sent to us, which is also why it works on a slow connection, only the page downloads, not your file.

Need a transcript of the audio?

Autrans also transcribes audio in Nigerian English, Pidgin, Yoruba, Hausa, Igbo, French, and Spanish.