Quiet score
0/100
Estimated from construction and layout.
Neighbor walls
Footsteps from above
About this apartment
Example answersTap the answers that match. The estimate above updates as you go.
How the estimate works
Each answer maps to typical published sound ratings for that kind of construction. STC (Sound Transmission Class) rates how well a wall or floor blocks airborne sound like voices and TV. IIC (Impact Insulation Class) rates how well a floor blocks footsteps. Higher is better for both.
The numbers shown are field values: what a wall achieves in a finished building, usually 3 to 8 points below its lab rating because sound also leaks through outlets, ducts, gaps and the structure itself. US building codes require 50 in the lab, or 45 when tested in the field, between dwellings. Many buildings older than the 1980s were never built to that.
The quiet score combines the wall and floor estimates, weighted toward the walls if a bedroom shares one, and subtracts points for noisy neighbors like elevators and trash chutes. A wall test of the neighbor wall replaces the wall estimate.
Real buildings vary. Two units in the same building can differ by 5 points or more depending on workmanship. Treat the result as a range, not a verdict.
Measure a wall
Play steady noise on one side of a wall, then measure how much quieter it is on the other side. The phone doesn't need to be calibrated, because only the difference counts.
What are you testing?
Test noise
Plays steady pink noise. A Bluetooth speaker works best; a phone speaker is only loud enough to test doors and weak walls. You can also open this page on a second phone or laptop and play the noise there. Point the speaker at the wall from about 1 m away, and keep the volume the same for steps 2 and 3. No sound on an iPhone? Turn off silent mode.
Three recordings
-
Quiet side, noise off
Stand where you would listen for the neighbor, about 1 m from the wall, with the test noise off.
-
Loud side, noise on
Start the noise. Stand 1 to 2 m from the speaker and move the phone slowly around while it records.
-
Quiet side, noise on
Leave the noise playing. Go back to the quiet side, about 1 m from the wall, and move the phone slowly while it records.
Result
Example result
How much quieter, per frequency band (dB)
At least this much
Rating curve
How echoey is the quiet-side room?
Empty rooms make the neighbor louder than it will be once you move in. This adjusts the result to a furnished room.
Room noise
Example readingMeasure the background noise where you would sleep. Close the windows and stay still and quiet while it records.
–dB(A)
Background–L90
Average–Leq
Loudest–Lmax
Events–+10 dB jumps
Calibrate the microphone
Phone microphones aren't calibrated, so absolute readings can be off by 5 dB or more. Comparing apartments with the same phone is still meaningful. To improve accuracy, match this page to a trusted meter once, such as the free NIOSH SLM app on iPhone or a handheld sound level meter.
Play a steady sound (a fan, or the test noise from another device). Read the trusted meter, enter its reading, then hold this phone in the same spot and tap Measure.
This visit
Saved visits
Saved in this browser on this device.
On the tour
The quietest choice is usually a top-floor corner unit in a concrete building, with the bedroom away from the elevator and the street.
What the ratings mean
Walls (STC, field). What you hear from a neighbor with a quiet bedroom at night:
| Rating | What gets through |
|---|
Floors (IIC, field). Footsteps from the unit above:
| Rating | What gets through |
|---|
Neither rating covers deep bass below 125 Hz, so subwoofers, heavy footfalls on wood floors, and building machinery can be audible even when the ratings look good.
Typical ratings by construction
Lab ratings for common assemblies. Expect 3 to 8 points less in a finished building.
| Wall | STC |
|---|---|
| Wood studs, one layer of drywall each side, no insulation | 33–35 |
| Same, with insulation | 36–39 |
| Old plaster on wood lath | 36–42 |
| Steel studs, insulation, one layer each side | 42–48 |
| Concrete block, painted | 45–50 |
| Wood studs, insulation, resilient channel | 45–52 |
| Staggered studs, insulation | 46–50 |
| Solid brick party wall, 9 to 12 in | 50–55 |
| Poured concrete, 6 to 8 in | 53–58 |
| Double stud wall, insulation | 55–62 |
| Floor | STC | IIC |
|---|---|---|
| Wood joists, hardwood, drywall ceiling | 37–42 | 30–38 |
| Concrete slab, bare or tile | 50–55 | 25–35 |
| Concrete slab, wood on acoustic underlay | 50–55 | 50–58 |
| Wood joists, gypsum concrete topping, resilient ceiling | 55–60 | 50–55 |
| Wood joists, carpet and pad | 40–50 | 55–70 |
| Concrete slab, carpet and pad | 50–55 | 65–80 |
How accurate is this?
Estimate. Built from typical published ratings. Real buildings vary by 5 points or more because of workmanship, back-to-back outlets, shared ducts and sound traveling through the structure.
Wall test. Uses the same method as professional field tests (ASTM E336, ISO 16283): a level difference between two rooms, corrected for background noise and room echo, rated against the ISO 717 reference curve in octave bands. A phone mic, few positions and a small speaker make it rougher, about ±3 to 5 points. Bass below 125 Hz isn't measured, and a phone speaker can't reach the lowest bands at all.
Room noise. Phones aren't calibrated, so absolute levels may be off by 5 dB or more until you calibrate. Rooms quieter than about 30 dB(A) are near the microphone's own noise floor, so the real level may be lower than shown.