Where noise comes from
| Spot | Sound | How it feels |
|---|---|---|
| Entrance, self-checkout | Doors, beeps, footsteps | Intermittent, breaks focus |
| Printer, water fountain | Machines, chat | Short but frequent |
| Under an air vent | Steady airflow | High reading, yet some people find it less distracting |
| Aisle seats | Chairs scraping, people passing | Visual distraction too |
| Window corners | Traffic outside | Depends on the windows |
At the same level, sudden sounds (doors, chairs) are more distracting than steady ones (ventilation). That is why you should look at the Max and the Min to Max range, not just the average.
Five minutes per seat
- Place the phone on the desk, near ear height when seated.
- Measure each seat for five minutes. One minute is too much luck.
- Note the average and the range. A narrow range means evenly spread sound.
- Pick two or three candidates and measure again on another day.
For context, the WHO’s community noise guidelines suggest background noise in classrooms of around 35 dB(A) during lessons. It is a useful reference for a learning space, though not directly comparable to a phone reading.
Check the time of day too
Study spaces fill up after classes and work, and on weekends before exams. Libraries change after opening and around lunch. Measuring the same seat at different times shows patterns like "quiet in the morning, noisy after four".
Comparing seats in the app
One session per seat
In Focus Noise Meter, tap Start and stop each time you move, so each seat gets its own session. The focus suitability label (Very quiet to Very noisy) updates as you go.
Compare ranges in Records
Each row in Records shows the average dB and label, time, duration and the Min to Max range. Jot down which session was which seat.
The app’s focus suitability levels are below. In a reading room most readings should be Quiet or lower; long stretches of Moderate suggest moving.
| App reading | Focus suitability | What the app says |
|---|---|---|
| Below 40 dB | Very quiet | Library-level silence |
| 40 to under 50 | Quiet | A quiet space that suits focus |
| 50 to under 65 | Moderate | About cafe level |
| 65 to under 75 | Noisy | Easy to lose focus |
| 75 and above | Very noisy | Consider moving |
FAQ
Does it record while measuring?
No. The app only calculates the level and never records, stores or sends audio.
Isn’t a little background noise better than silence?
It depends on the task. See the cafe-noise creativity study.
Focus Noise Meter - dB Sound Level
It never records audio, only calculates dB levels, and your history stays on your phone. Free on Android.