Sound Meter - Decibelscope

Sound meter apps give you a number. How far can you trust it? Decibelscope shows only the range it can trust.

Every phone has a different microphone, so the same sound reads differently. Most apps never say so - they just show a big number.
Decibelscope first shows the range this phone can measure reliably, and for anything outside it, gives you the reason instead of a made-up number.

Who this is for
- Anyone tracking noise from upstairs neighbours or nearby construction
- Anyone bothered by noise at a cafe, office or workshop
- Anyone checking how quiet the room is while a child sleeps
- Anyone who wants to know not just the number, but whether to trust it

How it shows you
- Trusted range - see at a glance whether the current value is inside the range this device can be trusted.
- Too quiet: "Below this phone's floor". Too loud: "At the limit - input clipped". It never invents a value it cannot measure.
- Values before calibration are marked "estimate".
- If this device cannot turn off microphone processing (auto gain), the app tells you.

Fit it to your phone (calibration)
- Enter a reference reading - if you own a sound level meter, type what it reads at the same spot to set the offset.
- 30 seconds in a quiet room - measure the quietest sound this phone can read (its floor).

What you can do
- Real-time now / average (Leq) / peak dB
- A-weighted (dBA), C-weighted (dBC) or unweighted, Fast/Slow response
- Keeps measuring with the screen off - with notifications on, it logs noise while you sleep or construction noise while you are out.
- When you stop, the log keeps the average and peak, plus how many moments were outside the trusted range.
- CSV export - open the log in a spreadsheet or share it as a file.

Promises
- Sound is never recorded or stored. The app only computes loudness, and no sound leaves your phone.
- No account, no sign-in.

Please note
This app is not a medical device and does not diagnose or treat any condition. It is not meant as evidence in noise disputes.
Use a certified sound level meter where legal accuracy is required. Because of microphone limits, error grows at very high levels (roughly above 100 dB).