WAV and FLAC Specs for Music Distribution (2026)
Deliver one lossless stereo master at its native sample rate and bit depth. Spotify accepts 44.1 kHz or higher, prefers FLAC, and accepts PCM WAV; Apple accepts 44.1 to 192 kHz at 16 or 24 bit. Your distributor may impose a narrower upload spec, so check its current portal before exporting.
Lead visual
Streaming master readout
Loudness meter
Integrated LUFS
-14target
True peak
-1dBTP
Bit depth
24bit
Waveform after normalization
Audio · Mastering
Playback spec map
Decision
Master for translation, not just for maximum loudness.
Evidence
LUFS, true peak, file format, headroom, codec behavior, and the final exported master.
Risk
A master that feels exciting in the room can distort, turn down, or lose impact after delivery.
Good outcome
A master that survives platform normalization and still feels intentional.
This page is the file-spec corner of the mastering-for-streaming cluster. The loudness pages cover how loud to go and where to set your true peak. This one is narrower and more boring, which is exactly why people get it wrong: what bit depth, what sample rate, and what file format you hand to a distributor.
The short answer is a 44.1 kHz WAV at your native bit depth. The longer answer matters because a couple of small mistakes here (upsampling a 44.1 kHz master, dithering down to 16-bit when you didn't have to, sending a 48 kHz file built for video) quietly cost you quality or get a submission flagged. None of it is hard once someone lays out the real numbers.
I'll go through bit depth, sample rate, the WAV-versus-FLAC question, the Canada-versus-US distinction (there basically isn't one for streaming, and I'll show you why), and the one broadcast case where 48 kHz is the right call.
Spotify's accepted native sample-rate floor
Apple's accepted delivery resolutions
the only WAV format code Spotify accepts (PCM)
per track: send the highest-quality native stereo source
Key takeaways
- Keep the native resolution: 24-bit if the real master is 24-bit, 16-bit if that is the best source, and the sample rate used at mastering.
- Do not downsample a 48 or 96 kHz native master just to reach a generic 44.1 kHz target. Spotify explicitly asks for the native sample rate.
- Do not upsample a 44.1 kHz master to make the numbers look larger. It adds no source information and can create a misleading delivery history.
- Spotify requires WAV files in WAVE_FORMAT_PCM (code 0x0001). The WAVE_FORMAT_EXTENSIBLE variant (0xFFFE) is not accepted, and some DAWs export that by default.
- Artist location does not change a DSP's audio requirements. The receiving distributor or production sets the delivery spec.
- Stereo only. Most distributors reject or flag mono submissions unless the track is intentionally mono.
What bit depth and sample rate should I deliver to a distributor?
Start with the native master, then check the upload portal that will actually receive it. Spotify asks providers for the highest-quality native stereo source at 44.1 kHz or higher: 24-bit when that is the native master, and 16-bit only when no higher-depth master exists. Apple accepts 44.1, 48, 88.2, 96, 176.4, and 192 kHz at either 16 or 24 bit for ordinary catalog delivery.
A distributor can be narrower than the DSP behind it. CD Baby currently asks for stereo 16-bit/44.1 kHz WAV or FLAC, while TuneCore accepts that floor and recommends a higher-resolution WAV. That is why there is no honest one-line spec for every distributor. Preserve your native master, then make the least destructive export that satisfies the specific portal.
| Minimum accepted | Recommended / preferred | |
|---|---|---|
| Spotify provider delivery | 44.1 kHz or higher; 16-bit only if native | Native 24-bit stereo FLAC preferred; PCM WAV accepted |
| Apple catalog delivery | 16- or 24-bit; 44.1 to 192 kHz | Keep the real source resolution |
| Apple Digital Masters | Qualifying 24-bit source | Use Apple's approved tools and workflow |
| TuneCore upload | 16-bit / 44.1 kHz stereo WAV accepted | 24-bit / 192 kHz stereo WAV recommended by TuneCore |
| CD Baby upload | 16-bit / 44.1 kHz stereo | WAV or FLAC recommended |
| Any other distributor | Check its current upload page | Do not assume the DSP maximum is the portal maximum |
Apple Digital Masters sets its floor higher, at 24-bit. That's the one program where a 16-bit master genuinely won't meet spec. Everywhere else, 16-bit clears the bar.
Why 24-bit if listeners can't hear the difference
Bit depth is just how many amplitude levels each sample can take. 16-bit gives you 65,536 levels; 24-bit gives you 16,777,216. More levels means a lower noise floor and more dynamic range to work with.
The numbers: 16-bit tops out around 96 dB of dynamic range, 24-bit around 144 dB. Nobody listens to 144 dB of range, and your earbuds can't reproduce it. The extra room isn't for the listener. It's headroom that keeps rounding errors from piling up while the file moves through processing and conversion. You deliver 24-bit because that's the resolution your master already lives at, and dropping it early throws away precision for no reason.
Don't dither down to 16-bit yourself
If your master is 24-bit, deliver it 24-bit. Don't convert it down to 16-bit before upload unless a distributor specifically demands it. The platform or distributor does that conversion with its own dithering when it needs to. Doing it yourself first just means the audio gets re-processed twice.
Should a streaming master be 44.1 or 48 kHz?
Sample rate is how many snapshots per second the file holds. Nyquist's theorem says you need at least double your highest frequency to reproduce it cleanly. Human hearing tops out near 20 kHz, so 44.1 kHz (a 22.05 kHz ceiling with filter room above the audible band) covers the full range with margin.
If the finished master is 44.1 kHz, deliver 44.1. If it is natively 48 or 96 kHz and the distributor accepts that rate, keep it. Spotify's current provider guidance explicitly says not to downsample higher-rate native masters before delivery; Apple accepts both the 44.1 and 48 kHz families.
The same logic works in the other direction. Converting a 44.1 kHz master to 96 kHz does not recreate information that was never captured. A higher number is useful only when it reflects the real production master and survives the distributor's upload rules.
Does the delivery spec change for Canadian artists?
No. Spotify and Apple apply their audio requirements to the delivered asset, not the artist's country. A Canadian artist and a US artist using the same distributor face the same upload portal. What can change is the destination: a broadcaster, film production, vinyl plant, or immersive-audio provider may ask for a separate master.
If you're chasing sync, keep two masters
For a Canadian artist pursuing film or TV placements, keep a 48 kHz broadcast master and a 44.1 kHz streaming master from the same mastering session. Don't convert a 44.1 kHz streaming file up to 48 kHz for sync after the fact. Maintain both from the start rather than resampling one into the other.
Treat those as destination deliverables, not reasons to resample the only archive copy you have. Keep the highest-quality native master and create a separately labelled export when a production supplies a different spec.
WAV vs FLAC vs AIFF: which format to send
WAV is the safe default. It's uncompressed PCM audio, accepted by every major distributor and platform. One catch worth knowing: Spotify requires WAV files in format code 0x0001, WAVE_FORMAT_PCM. The WAVE_FORMAT_EXTENSIBLE variant, code 0xFFFE, isn't accepted, and some DAWs export that without telling you. If a clean WAV gets rejected for a reason you can't explain, this is a prime suspect.
| What it is | When to use it | |
|---|---|---|
| WAV | Uncompressed PCM, the industry-standard delivery format | Default for any distributor; use PCM 0x0001, not the extensible variant |
| FLAC | Lossless compression, about 50% smaller with zero data loss | Spotify prefers it for lossless; not every distributor accepts it for submission |
| AIFF | Apple's uncompressed lossless equivalent of WAV | Fine anywhere WAV is, identical quality |
FLAC is mathematically lossless, so a correctly encoded FLAC and WAV can carry the same audio data while FLAC uses less storage. Spotify openly prefers FLAC for provider delivery. Some third-party portals still narrow the accepted formats, so verify before assuming either file will upload.
What you never do is deliver a master as MP3 or AAC. Those are lossy. The platform transcodes your file to its own lossy codec at playback anyway, so handing over an already-lossy file stacks two rounds of compression and you get generation loss. Master to lossless, deliver lossless, let the platform do the final lossy step once.
Stereo is the requirement for most distributors. Some flag or reject mono files outright, unless the track is genuinely meant to be mono.
Dolby Atmos is a separate delivery path
If you're delivering spatial audio, none of the stereo specs above apply directly. Apple's current Dolby Atmos music profile requires a BWF ADM file, 24-bit LPCM at 48 kHz, conformance to the stereo reference, integrated loudness no higher than -18 LKFS, and true peak no higher than -1 dB TP. Those are delivery ceilings, not a command to force every mix to exactly those readings.
Apple requires a stereo source alongside the immersive asset. Atmos delivery is a provider-specific parallel workflow with its own identifiers, fees, destinations, timing, and correction rules, so verify the current distributor path before the mix is commissioned.
Which current file-spec sources should I check?
Frequently asked questions
Can I just export an MP3 and let the platform handle it?+
Use a lossless WAV or FLAC whenever your distributor accepts it. Some distributors technically accept MP3, but that makes an already-lossy file the source for later platform conversions. A lossless delivery keeps the native master intact and gives each service the cleanest source for its own playback formats.
My master is 16-bit/44.1 kHz. Should I convert it to 24-bit before uploading?+
No. Padding a 16-bit file to 24-bit adds no musical information. Deliver the native 16-bit master if that is the highest-quality source you have and the distributor accepts it. Apple accepts ordinary catalog deliveries at either 16 or 24 bit; the separate Apple Digital Masters program expects a qualifying 24-bit source.
What's the maximum file size or length distributors accept?+
It varies by distributor and I won't put a single number in their mouth without their page in front of me. A standard 24-bit/44.1 kHz stereo WAV of a normal song length is well within every major distributor's limits. Very long files or extremely high sample rates (192 kHz) are where you'd hit a ceiling. DistroKid for instance may reject 192 kHz outright. Check the distributor's upload page if you're delivering something unusually long or high-res.
Does the file format affect my LUFS or true peak readings?+
The format itself doesn't change the measured loudness of identical audio. A WAV and a FLAC of the same master read the same LUFS and the same true peak. Where format matters is the final lossy transcode the platform applies: that step can push inter-sample peaks higher, which is exactly why the true-peak guide in this cluster recommends leaving -1 dBTP of headroom regardless of your delivery format.
Should I add metadata like ISRC and artist name into the WAV file itself?+
For distribution, what matters is the distributor's submission form, not tags baked into the audio file. The ISRC, titles, contributors, and credits reach the DSPs through those fields. Fill the platform's fields carefully. That's what the stores read.
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Keep reading
Pillar guide
Mastering for Streaming
LUFS targets, loudness normalization, true peak limits, and file specs for every major DSP, written by a working producer.
Related guide
True Peak Limits
How true peak limiting works, why lossy codecs can push intersample peaks above 0 dBFS, and why -1 dBTP is the right ceiling for streaming delivery.
Related guide
Spotify LUFS Target
Why Spotify's -14 LUFS normalization level changes how you should master, and what to deliver to stop punishing your loudest tracks.
Related guide
Audio file prep
What audio to deliver, when a released file can be swapped, and where minor technical repair becomes a new creative recording.
Check your metadata before your distributor does
Run your titles, credits, copyright lines, and ISRC and UPC codes through the free checker and catch the rejection-bait errors before you upload. It all runs in your browser.