How it works
One speaker, one door, three steps
Speaker in the room Put the speaker in the room
Bluetooth or AirPlay, door open. If the speaker has its own knob, turn that up too. Any Bluetooth or AirPlay speaker, inside the room, door open. If the speaker has its own volume knob, turn that up too — the app only sees your phone's slider.
Take the reference outside Step outside and take the reference
Stand outside the open door, phone at chest height. Four tones — 125, 500, 1k and 4k Hz — play while you hold still.
You stay outside; only the door changes.
Close the door, repeat Close the door and repeat
Same spot, same volume, door shut. The difference between the two readings is what your door blocks.
The tones are loud — near 90 dB inside the room for a door that blocks 40. The app warns you about pets, children and anyone asleep before it starts.
The score
0 to 50, in plain language
42
dB blocked · Sound Isolation Score
Excellent
A practical estimate measured with your phone, not lab equipment — comparable to professional STC ratings.
The four-tone breakdown
125, 500, 1k and 4k Hz, weighted for speech. It's the difference between a gap under the door and a thin door — and it's where a fix shows up first. Home and above.
It locates. It never scores.
Phone upside-down, bottom microphone at the seam. Set a baseline and sweep the frame — tap to mark the loud spots, and the marks become a findings list. 10 seconds free. Hold the phone upside-down with the bottom microphone at the seam and sweep the frame. Set a baseline spot and everything reads relative to it — tap to mark the loud spots as you find them, and the marks become a findings list.
The heat ramp is deliberately not the rating palette: a hot spot tells you where sound gets through, never how good the door is. The findings list is a live tool — it clears when you close it. Free gets a 10-second preview; Home and above run it as long as you like.
What's in the app
Sound Isolation Score
One number from 0 to 50, weighted for speech, with a plain-language rating beside it.
Four-tone breakdown
125 / 500 / 1k / 4k Hz — see which pitches leak. Home and above.
Leak Scanner
Sweep the frame and find the gap instead of guessing. 10 seconds free, unlimited on Home and above.
Rooms, history & notes
Measure again after a fix and watch the number move. Home and above — and anything you measured while locked is kept, ready to open.
PDF report
Export a result with its breakdown — ready to hand to a landlord or a builder. Home and above.
Raw dB & USB mic
Per-tone decibel figures, and calibration for a USB reference microphone. Studio.
Before you start
What you need
Two things that skew a result
Your speaker's own volume knob. The meter only tracks your phone's slider — the check passes while the measurement still fails. The meter only tracks your phone's slider. If the speaker has a knob, turn that up too — the app can't see it, and the check will pass while the measurement still fails.
Reduce Loud Audio. Settings → Sounds & Haptics → Headphone Safety silently caps a Bluetooth speaker. In Settings → Sounds & Haptics → Headphone Safety, it silently caps what a Bluetooth speaker can output. It's the most common cause of a mystery-low score.
Pricing
Every plan measures the same way
What changes is how much you can keep, compare and export. Free is a trial, not a tier: three QuietScores on the house.
3 QuietScores, then the score locks
billed $38.00 a year
billed $77.00 a year
3 QuietScores, then the score locks
The full score on your first 3 · 10 seconds of Leak Scanner · no breakdown, no notes, no PDF
billed $38.00 a year
Unlimited QuietScores · four-tone breakdown · save, history & notes · unlimited Leak Scanner · PDF report
Get Homebilled $77.00 a year
Everything in Home · raw dB figures · USB reference mic
For professionals
Business · $149.00/yr QuietScore Business · $149.00/yr
or $19.99 a month
Everything in Studio, plus your logo and company name on every PDF you export. Everything in Studio, plus your logo and company name printed on every PDF you export. Unlimited QuietScores.
See the Business plan →Prices in USD. Local prices vary by App Store region. Prices in USD. Local prices and currency vary by App Store region. Annual plans are billed once a year; the monthly equivalent is shown for comparison.
Questions
What happens after the three free scores?
The measurement still runs — the score is what locks, and the app keeps it. Upgrade and it opens in full, breakdown included, with no need to measure again. Retakes count; measurements we can't stand behind, interrupted or too noisy, don't.
Walls, floors or ceilings? Can it measure walls, floors or ceilings?
A QuietScore needs something you can open and close, so doors and windows are the target. For a wall, the Leak Scanner will still show you where sound gets through.
Score lower than expected? My score came back much lower than expected
Check Reduce Loud Audio in Settings → Sounds & Haptics → Headphone Safety, and check your speaker's own volume knob. Either one caps the tone without the app being able to see it. More in Support.