Is your master
actually ready?
Drop your final master. In 30 seconds: a PASS/FAIL verdict, a readiness score, and the exact fix for anything that would hurt the release.
Drop your master here
WAV, AIFF or FLAC · or click to choose
in one pass
vs. Youlean & Ozone
to a verdict
audio stays on your device
The errors you can't hear
It sounds perfect on your monitors. That's the trap.
You bounce the final, it hits hard in the studio, you hit upload. Then the platform, the encode or the club rig quietly wrecks it — and by then it's public and permanent.
- 01Spotify turns your loudness downThe limiting you fought for is undone at their gain knob. You kept the squash and lost the transients for nothing.
- 02Your peaks clip on encodeSamples read under 0 dBFS in the DAW; the wave between them clips the second it becomes AAC.
- 03Your bass vanishes in monoClub subs and phones are mono. Out-of-phase low end cancels right where the drop should hit.
- 04Distributors reject it silentlyWrong sample rate, 32-bit float, a fade chopped mid-tail — bounced before anyone hears it.
Try it · drag your loudness
Your master's loudness
Loud and competitive — club, EDM, hip-hop territory. Streaming turns it down to match everything else; the density still pays off anywhere that doesn't normalize.
The 7.0 dB Spotify takes back is limiting you paid for in transients. The report shows this per platform for your actual master — and never tells you to turn it down.
What you get back
A verdict you can screenshot, and the exact fix for what's off
- A verdict and a scorePASS / CHECK / FAIL plus a Release Readiness Score out of 100 — the thing you screenshot.
- Every finding ends in a fixNo raw numbers without an answer. One plain-English sentence per issue, with the timestamp.
- Loud is never a lectureA loud master is a choice. You get the trade-off per platform, never 'turn it down'.
- Fix it, then prove itRe-check the revision and the report shows score before → after and which fixes landed.
Fourteen checks, one pass
Every release-killer, including the ones nobody catches
Loudness against every platform, intersample clipping, mono collapse, format validity, dead air, chopped tails — and the three that separate a finished record from a loud one: punch, tonal balance, width.
Beyond the single
Chase a record. Check a whole one.
Both included with Credits and Unlimited. One check per master; references are free.
Who built this
I'm Charlie Crown.
Miami-based producer, 50M+ streams, releases on Universal, Sony Music, Ultra and Dim Mak. I've mastered records that charted — and still caught myself about to upload a master with a clipped peak I couldn't hear.
“So I built the tool I wish I'd had: the 30-second check before you hit distribute.”
Pricing
Start free. Pay only if you check constantly.
A mastering engineer charges $50–150 a track to catch this. A clipped release is permanent. Your first check every month is free; five more that never expire are $9.
Free
For the occasional final check.
No card required
Credits
For the producer shipping a few releases.
One payment · yours forever
Unlimited
Best valueFor engineers and prolific producers.
≈ $10.00/mo · two months free vs monthly
Cancel anytime · self-serve billing
Secure checkout by Stripe. Your card details never touch our servers. No refunds on credits or completed checks; subscriptions cancel anytime.
Questions
The honest answers
Is my audio really private?
Yes. The analysis runs entirely in your browser with WebAssembly — your file is never uploaded, transmitted, or stored, and it's discarded when you close the tab. Our servers only ever receive the resulting numbers.
How accurate is it?
Loudness (LUFS-I) and true peak match Youlean Loudness Meter and iZotope Ozone within ±0.1 — the same references mastering engineers rely on. It's the BS.1770-4 standard, not an approximation.
Will it tell me to turn my master down?
No. Loud is a creative choice, so a loud master never warns — you get the trade-off in plain terms (what streaming normalization does, what a club system does) and you decide. The only loudness warning is a master that's unusually quiet.
Will it master my track for me?
No, and that's the point. It tells you exactly what's technically wrong and how to fix it. The creative decisions stay yours.
Is it actually free?
Yes — one full check every month, no credit card, no trial clock. You only pay if you check masters often enough to want more.
What counts as a check?
One master analyzed and its report unlocked. Re-running the same file is a new check. A Reference Match comparison is one check (your master); the reference track is free. Album mode is one check per track.
Stop guessing before you hit distribute
Thirty seconds now beats a permanent mistake later. Free to start, and your audio never leaves your device.
NO UPLOAD · NO CARD · 30 SECONDS