Step 1: Provide your AAC files using the button above or by toss and let go.
Step 2: Click the 'Convert' button to start the conversion.
Step 3: Fetch 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 / bitrate combination that matches the source profile. Lossless FLAC (WAV / FLAC / ALAC) preserves every sample exactly; lossy FLAC (MP3 / AAC / OGG / Opus) defaults to 192 kbps which is transparent for almost all music content.
What bitrate does the FLAC file end up at?
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Default 192 kbps for lossy FLAC; pass-through for lossless FLAC. Override to 320 kbps if you want maximum lossy fidelity, 128 kbps for size-constrained podcast distribution, or 96 kbps for voice-only sources where the smaller file matters more than studio detail.
Will going from AAC to FLAC actually reduce my audio quality?
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If AAC is lossy (MP3, AAC) and FLAC is lossless (WAV, FLAC), the FLAC is no better than the AAC — you cannot recover information already discarded by the lossy AAC codec. If AAC is lossless and FLAC is lossy, expect the FLAC encoder to recompress; at 192 kbps the loss is imperceptible to most ears.
Does the AAC to FLAC converter keep ID3 / metadata tags?
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Yes — title, artist, album, year, track number, album art, BPM, replay-gain are read from the AAC container and written into the equivalent fields on the FLAC container. ID3v2 (MP3), Vorbis comments (OGG, FLAC), MP4 atoms (AAC, M4A), RIFF INFO (WAV), iXML chunks all map cleanly.
Can I batch-convert hundreds of AAC files into 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. Folder structure is preserved in the output ZIP.
Will the FLAC keep the same sample rate as the AAC?
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By default yes (a 48 kHz AAC produces 48 kHz FLAC, a 44.1 kHz AAC produces 44.1 kHz FLAC). For specific compatibility — e.g. downsampling 96 kHz studio masters to 44.1 kHz FLAC for CD burning, or upsampling 22 kHz voicemail to 44.1 kHz FLAC — the sample-rate dropdown applies high-quality SOX-style resampling.
Can I normalize loudness in the AAC to FLAC step?
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Yes — the loudness-normalize option applies ITU-R BS.1770 / EBU R128 normalization to the FLAC output, targeting -14 LUFS (streaming standard) or -16 LUFS (podcast standard) or a custom value. Useful when batch-converting tracks with varying mastering levels into a single FLAC playlist.
Will the FLAC play on my car stereo / iPod / Sonos / Bluetooth speaker?
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MP3 plays universally on every device made in the last 20 years. AAC plays on Apple, most Android, Sonos, and modern car stereos. FLAC plays on Sonos and recent Android, less well on older iPods. WAV plays on everything but the file is huge. The device-target dropdown picks a safe FLAC codec for the platform you specify.
Is my AAC file private during conversion?
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Yes — uploaded AAC files are processed in isolated workers and deleted within minutes. We never play, store, or share the audio content. The pipeline runs on hardware we control end-to-end; no third-party services receive your file.
How long does converting a 1-hour AAC to FLAC take?
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Same-codec re-mux (e.g. AAC inside M4A -> AAC inside MP4): 10-30 seconds. Codec change (e.g. FLAC -> MP3 or WAV -> AAC): typically 10-20% of source duration, so a 1-hour AAC -> FLAC finishes in 6-12 minutes on the standard pipeline.
Why is the FLAC file louder or quieter than the AAC source?
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No automatic gain change happens unless the normalize option is turned on. If you do hear a level shift, your audio player or media library may be applying ReplayGain or per-track normalization on playback — turn that off and the FLAC sounds bit-identical to the AAC (for lossless) or perceptually identical (for transparent lossy).
Can I convert AAC downloads from Bandcamp / SoundCloud into FLAC?
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If the AAC download is unprotected (no DRM), yes. DRM-encrypted streaming files (Spotify offline, Apple Music) are encrypted at the bit level and cannot be processed. Sources from Bandcamp purchases, SoundCloud go downloads, podcast feeds, and personal recordings all convert cleanly into FLAC.