Step 1: Transfer your AAC files using the button above or by slide and deposit.
Step 2: Click the 'Convert' button to start the conversion.
Step 3: Retrieve your converted FLAC files.
AAC to FLAC Conversion FAQ
How do I convert AAC audio to FLAC without losing quality?
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Upload the AAC file and the converter chooses the FLAC codec and bitrate to match the source. Lossless FLAC (WAV / FLAC / ALAC) preserves every sample bit-identically; lossy FLAC (MP3 / AAC / OGG / Opus) defaults to 192 kbps which is transparent for most ears. AAC is lossy but more efficient than MP3, and it handles up to 48 channels natively rather than being bolted onto a stereo design. FLAC uses linear prediction plus Rice coding to reach roughly 50-60% of the original size while decoding back to bit-identical PCM.
Does converting AAC to FLAC improve the audio quality?
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No, and it is worth being blunt: nothing can. The AAC already discarded detail during its original encode, and wrapping what remains in a lossless FLAC preserves exactly that — no more. The file gets several times larger and sounds identical. It is still the right move before editing, because FLAC will not add a second generation of artefacts when you export. FLAC gives you WAV fidelity at half the size, with proper metadata tags and embedded artwork, which is why it dominates lossless music libraries. AAC is patent-encumbered, and a handful of very old players still refuse it where they would accept an MP3.
Will the FLAC play in my car or on older hardware?
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Often not. AAC is decoded by essentially everything, including car head units and elderly players; FLAC needs software that knows the codec, which standalone hardware frequently does not have. If the destination is a car stereo or a portable player, that is a strong argument for staying on AAC. FLAC is still several times larger than a good lossy file, and Apple’s ecosystem only added support recently and grudgingly.
What bitrate will the resulting FLAC file use?
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Default is 192 kbps for lossy FLAC; pass-through for lossless FLAC. Override to 320 kbps for audiophile or 96 kbps for voice / podcast. The choice trades file size against audible fidelity; below 96 kbps lossy artifacts become noticeable on music.
Will going from AAC to FLAC reduce my audio quality?
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If AAC is lossy and FLAC is lossless (e.g. MP3 → WAV), the FLAC is no better than the AAC — you cannot recover information already discarded. If AAC is lossless and FLAC is lossy, the FLAC codec recompresses; at 192 kbps the result is transparent for most content.
Does the AAC to FLAC converter keep ID3 / metadata tags?
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Yes — title, artist, album, year, track number, and album art are read from the AAC container and written into the FLAC container where the format supports tags. All common targets (MP3, AAC, FLAC, OGG) handle tags fine; raw WAV does not. FLAC is the Free Lossless Audio Codec, an open format from 2001 that compresses without discarding a single sample.
Can I batch convert hundreds of AAC files to FLAC?
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Yes — drop a folder of AAC files in and we process them in parallel. Premium has more parallel workers and no per-file size cap, so a 500-file batch finishes in minutes rather than tens of minutes.
Will the FLAC keep the same sample rate as AAC?
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By default yes — 48 kHz AAC stays 48 kHz in FLAC. If you need to downsample for compatibility (96 kHz → 44.1 kHz for CD burning), the sample-rate option applies high-quality resampling in the same encode pass.
Can I normalize loudness when converting AAC to FLAC?
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Yes — the loudness-normalize option applies ITU-R BS.1770 / EBU R128 normalization to the FLAC, targeting -14 LUFS (streaming standard) or -16 LUFS (podcast standard). Useful when batching tracks mastered at varying levels.
Will my FLAC play on car stereo, iPod, and Sonos?
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MP3 plays everywhere. AAC plays on Apple, most Android, and Sonos. FLAC plays on Sonos and Android but not on older iPods. WAV plays on everything but is huge. The advanced device-preset dropdown picks a FLAC codec optimized for your target hardware.
Is my AAC file private during conversion to FLAC?
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Yes — uploaded AAC files are processed in isolated workers and deleted within minutes. We never play back, store long-term, or share the audio content. The full retention window is in /privacy/.
How long does converting a 1-hour AAC to FLAC take?
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Same-codec re-mux: 10 to 30 seconds. Re-encode to a different codec: typically 10 to 20% of source duration, so a 1-hour AAC → FLAC finishes in 6 to 12 minutes. Batch jobs parallelize across workers for further speedups.
