FLAC vs WAV for Mastering
Published · updated · by Loopin
FLAC and WAV sound identical: both are lossless, so a FLAC decodes to exactly the same audio as the WAV. Use WAV for anything you send, master or deliver, and FLAC only to archive finished files at roughly half the size.
Stop worrying about sound quality
FLAC compresses audio the way a ZIP file compresses a document: nothing is thrown away, and the decoded file is bit-for-bit identical to the original. That’s the opposite of MP3 or AAC, which discard information permanently. A WAV and a FLAC of the same master, played back, are the same audio.
So anyone telling you WAV “sounds warmer” or FLAC “sounds tighter” is hearing a level difference or a different source file. If you’re choosing between lossless and lossy, that’s the decision that matters; see WAV vs MP3 for mastering.
Use the format that fits each step
Sending a mix to be mastered: WAV. Every DAW, plugin and mastering service reads it, and it avoids one more conversion. Delivering a master to a distributor: WAV, unless the distributor’s spec sheet says otherwise; most ask for WAV. Archiving finished masters and mixes: FLAC, for the smaller size and better tagging.
Sharing a lossless copy with a collaborator: either, but WAV if you’re not sure what software they use. Streaming playback: it doesn’t matter what you upload, because services re-encode everything to their own formats.
Know where each one actually wins
WAV wins on compatibility. It opens everywhere, needs no decoding, and is the default upload format for distributors and online mastering tools. Its weaknesses: large files, and metadata support that varies between programs.
FLAC wins on storage and tagging. Files are typically around half to two-thirds the size of the WAV, and tags for title, artist, ISRC and artwork are reliable. Its weakness: some tools, older DAWs and upload forms still don’t accept it, which is exactly where a last-minute conversion goes wrong.
Master from a WAV and get a WAV back
The simplest safe workflow: bounce your mix as a WAV at the project sample rate, 24-bit if you can, peaks around −6 to −3 dBFS. Upload it to free online mastering, which also accepts MP3 and most common formats, and you’ll get a 16-bit WAV back at about −14 LUFS with a −1 dBTP ceiling, ready for distributors.
If your only copy of the mix is a FLAC, convert it to WAV first; it’s lossless, so nothing is lost. Then master the WAV free and archive the result as FLAC if you want the space back.
Skip these format mistakes
Don’t convert an MP3 into WAV or FLAC and call it lossless; the loss already happened. Don’t convert back and forth between formats repeatedly for no reason; it’s harmless with lossless files but a common place to accidentally change sample rate or bit depth. And don’t pick a format to “improve” sound; neither one will.
Bit depth and sample rate matter far more than the container. If that’s your real question, read 24-bit vs 16-bit for mastering.
Frequently asked questions
Is FLAC better than WAV?
Neither sounds better. Both are lossless and decode to identical audio. FLAC is smaller and tags better; WAV is more widely accepted.
Should I send FLAC or WAV for mastering?
WAV. It's accepted by every DAW and mastering tool, so it avoids a conversion step. Send it at the project sample rate, ideally 24-bit, with peaks around -6 to -3 dBFS.
Can I upload FLAC to a distributor?
Some accept it, many ask for WAV. Check your distributor's current upload requirements, and use WAV if you're unsure.
How much smaller is FLAC than WAV?
Typically around half to two-thirds of the WAV's size, depending on the music. Dense, loud tracks compress less than quiet, sparse ones.
Does converting FLAC to WAV lose quality?
No. FLAC to WAV is lossless as long as you keep the same sample rate and bit depth.
Is FLAC better for archiving masters?
Yes. It saves space with no quality loss and stores tags like title, artist and ISRC reliably.
What format does free online mastering give back?
Loopin's free online mastering returns a 16-bit WAV at about -14 LUFS with a -1 dBTP ceiling, which distributors accept. Archive it as FLAC afterwards if you want to save space.
Does Spotify care if I upload FLAC or WAV?
No. Your distributor passes the file on and Spotify re-encodes it to its own streaming formats, so both end up sounding the same to listeners.