Is FLAC to WAV lossless?

No codec loss is added, because nothing is compressed again, but it is not a bit-for-bit copy. The decoded samples pass through 32-bit floats and are written back at 16 bits, so a 24-bit FLAC is rounded to 16 bits, and a FLAC whose sample rate differs from the one you pick is resampled by linear interpolation, which is an approximation. Pick the FLAC's own rate, 44.1 or 48 kHz, to avoid resampling.

How do I convert FLAC to WAV?

Leave From on WAV, which is the mode a FLAC opens in, and To on WAV, press Open audio or drop the FLAC on the stage, pick the sample rate and channels, press Convert and then Download. The stage says it found a FLAC before anything is decoded.

Why is the WAV so much bigger than the FLAC?

FLAC packs PCM losslessly, typically to about half its size or a little more, and the WAV stores it unpacked. One minute of 44.1 kHz 16-bit stereo is 10.1 MB as a WAV whatever it came from.

What if my browser cannot decode FLAC?

The page asks your browser before converting, and if it has no FLAC decoder the message says so and nothing is started. Most current browsers decode FLAC; trying another one is the quickest fix.

Is the FLAC uploaded?

No. It is decoded in this tab and the WAV is written here, so the file never leaves your device.

FLAC to WAV Converter

Open a FLAC and this page identifies it by its first bytes, decodes it with your browser's own FLAC decoder and writes the samples as an uncompressed 16-bit WAV. A FLAC opens in WAV mode, because it holds the same kind of PCM a WAV does, packed losslessly. The WAV size is exact arithmetic and is shown before you convert.

Open a WAV or FLAC file

· or drop one anywhere on the stage

Never uploadedNo accountUp to 50 MBUp to 10 minutes

From · opens WAV or FLAC

Bit depth

Sample rate

Channels

Download

Ready. Choose a WAV or FLAC file, or drop one on the stage.

A WAV is read as PCM, and 24-bit samples are scaled by 2^23 into the encoder rather than truncated. A FLAC opens here too, unpacked by this browser's own FLAC decoder. The output is uncompressed 16-bit PCM at the sample rate you choose, which does not restore anything a lossy file already lost: it is a larger file, not a better one.

What the bytes sayread from the first bytes of the file, never from its extension
Open a file and its container is identified before anything is decoded.
Output sizeexact arithmetic for PCM, an estimate for MP3
Open a file to size the output.
Decoderasked of this browser before a conversion starts
A codec with no decoder here is named up front, not halfway through.

The From control is a mode, not a guess: the first bytes of the file are read and checked against it, so a file that was renamed is refused with what it actually is. A bare AAC opens in M4A mode, and a MOV or WebM video in MP4 mode. An MP4 has its audio tracks listed before anything is extracted and its video is never decoded. Changing the sample rate resamples by linear interpolation, and changing the channel count averages a stereo pair down or copies a mono channel to both sides.

Two open source parts do the heavy lifting. Containers are parsed and audio is decoded by Mediabunny 1.55.7 under the MPL-2.0 (licence text, the exact package, source). MP3 encoding is lamejs 1.2.7 under the LGPL-3.0 (licence text, the exact package, corresponding source). Both are bundled unmodified at those versions and loaded from this page, never from another service.

Common questions

Is FLAC to WAV lossless?: No codec loss is added, because nothing is compressed again, but it is not a bit-for-bit copy. The decoded samples pass through 32-bit floats and are written back at 16 bits, so a 24-bit FLAC is rounded to 16 bits, and a FLAC whose sample rate differs from the one you pick is resampled by linear interpolation, which is an approximation. Pick the FLAC's own rate, 44.1 or 48 kHz, to avoid resampling.
How do I convert FLAC to WAV?: Leave From on WAV, which is the mode a FLAC opens in, and To on WAV, press Open audio or drop the FLAC on the stage, pick the sample rate and channels, press Convert and then Download. The stage says it found a FLAC before anything is decoded.
Why is the WAV so much bigger than the FLAC?: FLAC packs PCM losslessly, typically to about half its size or a little more, and the WAV stores it unpacked. One minute of 44.1 kHz 16-bit stereo is 10.1 MB as a WAV whatever it came from.
What if my browser cannot decode FLAC?: The page asks your browser before converting, and if it has no FLAC decoder the message says so and nothing is started. Most current browsers decode FLAC; trying another one is the quickest fix.
Is the FLAC uploaded?: No. It is decoded in this tab and the WAV is written here, so the file never leaves your device.

Files are decoded and re-encoded in your browser, so nothing is uploaded. Converting cannot restore detail a lossy file already lost, and an MP3 output is a lossy encode of its own. Which formats can be decoded depends on your browser, and this page checks the file's actual bytes and its codec before starting rather than trusting the extension.