Mastering Studio
Online mastering service: four masters of your mix, every change explained
Upload a finished stereo mix and one run gives you four 24-bit WAV masters, from streaming-ready Dynamic to chart-loud Chart. You compare them at the same loudness and read what was changed and why.
Mastering is for Supporters: 20 runs a month included, then 85 tokens per run. Each run gives you all four masters. Check your mix first with the free analyzer
- 4 masters per run
- 24-bit WAV
- Equal-loudness A/B
- Upload deleted after the run
Hear one mix become four masters
Thirty seconds from a real run with default settings. With equal loudness on, like in the studio, the louder clips are turned down to the quietest, so you hear tone and punch instead of volume. Switch it off to hear how loud each master really is.
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Original mix
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Dynamic
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Balanced Recommended
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Loud
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Chart
What changed in the Balanced master
- Source: Recorded (Auto)
- Sub Bass: +1.0 dB, it measured below a balanced master
- Highs: +2.5 dB, it measured below a balanced master
- Air: +1.5 dB, it measured below a balanced master
- Air: +0.8 dB of sheen, part of this master's character
- Sides above 300 Hz widened +0.8 dB, part of this master's character (the low end stays centred)
- Glue compression: −2.1 dB on the loudest parts, 2:1
- Limiter: −1.1 dB on loud passages, −5.9 dB on the biggest hit
Demo track: “Sailing Through The Trees (Draft-1)” by Ten Letters, public domain (CC0 1.0). Excerpt 1:44–2:14, compressed for the web. Your masters are 24-bit WAV. Original on the Internet Archive
Four masters from one online mastering run
Every run puts your mix through the same corrective chain at four densities, and past Dynamic each master gets a little wider and brighter. Pick by sound first, then by where the track is going.
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Dynamic
Target −14 LUFS, ceiling −1 dBTPFor streaming. Spotify, YouTube and Tidal play music at about −14 LUFS, so this master keeps all of its dynamics and adds no width or sheen.
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Balanced
Target −11 LUFS, ceiling −2 dBTPA little denser, wider and brighter. The studio suggests this one first unless your genre or a very dynamic mix points elsewhere.
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Loud
Target −8.5 LUFS, ceiling −2 dBTPDense and forward, wider and brighter again, for club tracks, EDM and heavy genres.
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Chart
Target −7.5 LUFS, ceiling −1 dBTPAs loud as current chart releases and the widest and brightest of the four, with a soft clipper ahead of the limiter.
These are targets. When a target would squash your drums, the master stops quieter and says so. You can move all four from −3 to +1.5 LU. The extra width never touches the low end and is skipped on mixes that are already wide.
How online mastering works here
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Upload your mix
WAV, FLAC, AIFF, MP3, M4A, AAC or OGG, from 3 seconds to 12 minutes and up to 95 MB. A lossless export with peaks around −6 dBFS works best.
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Shape it, or leave it on Auto
Style, tone, stereo width, punch, loudness, mono bass, de-harsh and source are all optional. On Auto, the settings come from measuring your mix.
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Run all four masters
One run renders all four masters while you follow the progress. If it fails, your tokens or included run come back automatically.
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Compare and download
Switch between your mix and the masters at the same loudness, read what changed in each, and download the WAV you like. Supporters keep their masters for 30 days.
What one-click mastering doesn't show you
Every change, with the reason
Each master lists its EQ, compression and limiting in plain words and marks what came from your settings. Corrective EQ stays within 3 dB per band, so the mix is corrected, not rebuilt.
Comparison at the same loudness
A louder version always sounds better for the first few seconds. The studio turns the louder masters down to match the quietest, so you judge tone and punch instead of volume.
Loudness that stops before it squashes
When reaching a target would take heavy limiting, the master stays quieter and tells you. Streaming services turn loud masters down anyway.
Your upload is deleted
The mix you upload is deleted as soon as the run ends, even if it fails. Masters are deleted after 30 days on a Supporter account and after 24 hours otherwise, unless you keep a run.
Master your AI-generated songs
Songs from Suno, Udio and other generators sound finished but are rarely ready for release: the top end is often cut off, the low end uneven and the loudness all over the place. Our mastering targets are calibrated on AI-generated songs as well as on recorded, professionally mixed tracks.
- Source on Auto recognises AI-generated music with the same detector as the mix analysis report.
- AI songs never get the air band above 10 kHz boosted, because generators leave artefacts there, and they get a slightly darker treble target.
- Recorded mixes get a brighter treble target, checked against professional mixes.
- Always upload a WAV in the highest quality the generator offers. An MP3 has already lost part of the top end.
Hear a Suno song mastered
An MP3 straight from Suno, mastered with default settings. Source on Auto recognised it as AI-generated, so the air band was left alone.
For your own songs, always upload a WAV in the highest quality you can export. We used Suno's MP3 here only for the demo.
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Original mix
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Dynamic Recommended
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Balanced
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Loud
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Chart
What changed in the Dynamic master
- Source: AI-generated (Auto)
- Sub Bass: −1.2 dB, it measured above a balanced master
- High Mids: +0.4 dB, it measured below a balanced master
- Glue compression: −1.1 dB on the loudest parts, 1.5:1
- The limiter only caught peaks (at most −0.5 dB)
Demo song: “Its me”, made with Suno. Excerpt 0:32–1:02, compressed for the web. Your masters are 24-bit WAV.
When to fix the mix before mastering
Mastering polishes a finished mix. It can't bring up a buried vocal, tame a boomy kick or undo clipping, and the results tell you when they find a problem like that instead of hiding it under a limiter.
Not sure the mix is ready? The free mix analysis scores balance, dynamics, stereo and loudness and tells you what to fix first.
Not offered: stem mastering, Dolby Atmos, album sequencing and DDP files.
Analyze your mix for freeOnline mastering price
- Mastering is for Supporters, with 20 runs a month included. Each run gives you all four masters.
- After the included runs, a run costs 85 tokens. Tokens come in one-time packs and don't expire.
- A failed run gives your tokens or included run back automatically.
- The account is free, and so are 2 mix analyses a month.
Online mastering FAQ
How much does online mastering cost?
Mastering is for Supporters. Supporter includes 20 runs a month, and each run gives you four masters. After that, a run costs 85 tokens. Current prices are on the pricing page.
Is there free online mastering here?
No. The account and 2 mix analyses a month are free, but mastering is for Supporters: 20 runs a month are included, then 85 tokens per run. A failed run is always refunded.
Which master should I upload to Spotify?
Dynamic or Balanced. Spotify plays music at about −14 LUFS, so a louder master is turned down and keeps only its extra density.
How do I choose between the four masters?
Listen at the same loudness, which the studio does for you, and keep the one whose punch and tone you like. The studio also suggests one to start with.
Is this AI mastering?
The studio measures your mix and applies capped EQ, compression and limiting based on those numbers, then lists every move. Machine learning recognises AI-generated music, so those songs get a target made for them.
Can I master a Suno or Udio song?
Yes. Leave Source on Auto or choose AI-generated. AI songs never get the air band above 10 kHz boosted, so the generator's artefacts don't get louder.
What files can I upload, and what do I get back?
WAV, FLAC, AIFF, MP3, M4A, AAC or OGG, up to 12 minutes and 95 MB. You get four 24-bit stereo WAV files at your mix's sample rate, up to 48 kHz.
How should I prepare my mix for mastering?
Export the finished stereo mix as WAV or FLAC, without a limiter or clipper on the mix bus, with peaks around −6 dBFS. Run the free mix analysis first if you want a full check.
What happens to my song after upload?
Your upload is deleted when the run ends, even if it fails. The four masters stay in My masters for 30 days on a Supporter account and 24 hours otherwise, then they are deleted. You can keep a run's masters until you delete them for extra tokens, and each run's report stays until you delete it.
Can I release the masters on Spotify and Apple Music?
Yes. They are standard 24-bit WAV files with true-peak ceilings of −1 or −2 dBTP, the kind of file distributors ask for.
Is there a mastering API?
Yes. Supporters can start runs and download the masters with POST /api/mastering.
Ready to master your mix?
Four masters per run, compared at the same loudness, with every change explained.
Mastering is for Supporters: 20 runs a month included, then 85 tokens per run. Each run gives you all four masters.