Convert AAC to FLAC in seconds, free and entirely in your browser. AAC is the efficient lossy codec used by Apple and most streaming services; FLAC is losslessly compressed audio, ideal for archiving. Transcodr runs real ffmpeg compiled to WebAssembly, so your file is processed on your own device and never uploaded.
Drop files to convert
Video, audio, images, subtitles: anything ffmpeg can read. Drop them anywhere on the page or browse from disk.
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When you convert something, it’ll appear here. Clears on tab close — we don’t keep records.
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Release to add to the conversion queue.
AAC vs FLAC
Property
AAC
FLAC
Compression
Lossy
Compressed
Fidelity
Efficient
Lossless
File size
Small
Medium
AAC → FLAC questions
Is the AAC to FLAC converter free?
Yes. Transcodr is free with no accounts, watermarks, or hard limits beyond your device's available memory.
Are my files uploaded to a server?
No. The conversion runs locally via ffmpeg compiled to WebAssembly, so your AAC file never leaves the browser tab.
What quality is the FLAC output?
FLAC — lossless — a lossless result, so no audio quality is lost (files are larger).
How do I convert AAC to FLAC?
Drop your AAC file above (or click Browse) — the output is already preset to FLAC — then click Convert and download the result.
01 / Engine
Real ffmpeg, compiled to WebAssembly.
Same library Netflix, YouTube, and basically every command-line video tool relies on, running in a Web Worker. Pipe a file in, run a command, pipe bytes back out.
02 / Privacy
Nothing leaves the tab.
No uploads, no accounts, no telemetry beyond an anonymous pageview. We couldn’t see your files if we wanted to — there’s no server in the loop.
03 / Limits
It is, after all, a tab.
Files up to a few hundred megabytes convert comfortably. Beyond that, your browser starts asking pointed questions. Use the desktop ffmpeg for 4K masters.