Add your MMF file
Drop one or more .mmf files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
Re-encoding .mmf audio as .flac changes how the sound is compressed and which players will accept it. Free, private, and validated — the file never leaves your browser.
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.Re-encoding .mmf audio as .flac changes how the sound is compressed and which players will accept it. An .mmf file is a Yamaha SMAF (Synthetic music Mobile Application Format) file, the ringtone format of early-2000s mobile phones. Rather than a recording, an .mmf usually contains sequenced music that a phone's Yamaha synthesizer chip performed live, sometimes blended with short PCM samples.
A .flac file contains audio compressed with the Free Lossless Audio Codec, which shrinks recordings without discarding a single sample. Decoded .flac output is bit-identical to the source, so the format has become the standard for music archiving and high-resolution downloads. For this route the practical draw is genuinely lossless while roughly halving storage and open specification with no royalties anywhere in the chain — balanced against still several times larger than a good lossy encode, which is worth knowing before you commit a large batch.
The practical trigger for this conversion is usually a mismatch: with .mmf, no current phone, browser, or OS plays it at all. Switching to .flac buys you genuinely lossless while roughly halving storage, which is why it is the better fit for ripping CD collections for permanent archival. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.
| Aspect | SMAF mobile audio (.mmf) | FLAC audio (.flac) |
|---|---|---|
| Format type | Lossy — discards detail it judges invisible to shrink files | Lossless — every pixel or sample is preserved exactly |
| How it stores data | a chunk-based format conceptually close to MIDI, with score tracks driving FM and wavetable synthesis | linear prediction followed by Rice coding typically yields files 40 to 60 percent the size of raw PCM |
| Strongest at | preserving ringtone collections from early-2000s handsets | ripping CD collections for permanent archival |
| Weak spot | no current phone, browser, or OS plays it at all | still several times larger than a good lossy encode |
| Metadata | optional contents-info chunks can name the title, artist, and copyright, fields Yamaha included for the commercial ringtone market | vorbis comments for tags plus a dedicated PICTURE block for cover art; cue sheets can be embedded for whole-disc rips |
Drop one or more .mmf files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
Select .flac in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if FLAC is selectable, the route is real and validated.
Press Convert. The transcode runs on an FFmpeg engine compiled to WebAssembly, so the audio never leaves your device.
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid FLAC file. Outputs keep the original filename with the .flac extension.
No new loss is introduced — since mmf is lossy-oriented and flac is lossless-oriented, everything the .mmf file still contains is carried over exactly. What was already discarded by the original lossy encode cannot be recovered, though; converting to .flac does not "restore" quality.
Yes — the .mmf file is processed inside your browser tab and never uploaded. The transcode runs on an FFmpeg engine compiled to WebAssembly, so the audio never leaves your device. Close the tab and the file is gone from memory.
All major browsers decode .flac, Windows 10 and later plus Android play it natively, and virtually every dedicated audio player supports it. The persistent gap is Apple's Music ecosystem, where converting to ALAC delivers the same audio in a supported wrapper.
Larger, sometimes much larger. A lossless .flac must store every pixel or sample the decoder produced, without the perceptual shortcuts .mmf used. Use this route for editing headroom, not for saving space.
This converter strips container metadata deliberately (the FFmpeg command runs with metadata mapping disabled) so exported files do not leak recording details. In the source, optional contents-info chunks can name the title, artist, and copyright, fields Yamaha included for the commercial ringtone market; none of it is transmitted anywhere because the file never leaves your browser.