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FLAC to MP3

Compress a lossless FLAC down to MP3. This is the one direction here where real audio quality is thrown away on purpose, traded for a file roughly a tenth the size at the default quality setting.

Input

Options

FLAC to MP3 turns a lossless file into a compressed MP3 at a quality preset, medium by default. This is the only direction in this batch where genuine detail gets deliberately discarded, in exchange for roughly a tenth of the original byte count. Encoding needs WebCodecs, so a browser tab runs this page.

Questions

Is this the pair with the biggest quality trade-off?

Yes, of the ten audio pairs here. FLAC is lossless, so converting to MP3 is the one direction where real audio quality is thrown away on purpose, not only a second pass on an already lossy source.

How much smaller does the file get?

Roughly a tenth of the size at the default quality, similar to wav-to-mp3, since lossless FLAC still stores full audio detail that lossy MP3 encoding then discards.

Which engine handles this, and where can it run?

mediabunny and WebCodecs decode the FLAC, and mediabunny loads a LAME-based MP3 extension on demand as a separate chunk to encode the result. This is browser only; the command line and MCP refuse it and point to the web page.

What size should I expect?

A real MP3 well under the source FLAC size, with the exact ratio depending on the quality option, low, medium or high, medium by default.

What is the reverse page?

There is no dedicated mp3-to-flac page. Convert audio can write FLAC from an MP3 source, though it cannot restore anything the MP3 already discarded, since FLAC losslessness only applies from that point forward.

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