PoshanSenseA little less noise.
A little more awareness.
Use your phone or computer microphone to explore sound levels. Reference-adjust it against a trusted meter for a better estimate.
Without a reference measurement, this tool shows digital microphone level (dBFS), not environmental decibels. Even after adjustment, it is not a certified sound level meter or a test of hearing safety.
Microphone is off. Audio is processed on your device and is not recorded, saved or uploaded.
Live energy level · Fast response (125 ms)
Trend uses a fixed −90 to 0 dBFS digital scale, independent of reference adjustment.
Match a trusted reference
- Use a calibrated sound level meter alongside your device, with the microphones close together without touching or blocking either one.
- Choose the same weighting on both meters: A here with dB(A) on the reference, or unweighted here with an unweighted reference. Use a steady sound and wait for readings to settle. Do not use a phone speaker or an online tone as a known-decibel reference.
- Enter the reference reading below. We match the next five seconds of microphone energy to that reading. Recheck at other levels and with similar sound sources; one point cannot correct the microphone’s frequency response.
Adjustment stays only in this session and clears when you stop or restart. Changing microphone, gain, weighting, placement or device requires a new match. Avoid clipping and do not deliberately create loud sounds to calibrate.
Get the best measurement your device allows
- Use a measurement microphone with a known response and a suitable interface when possible. A built-in phone or laptop microphone has unknown sensitivity and may compress loud sounds.
- Keep microphone openings clear, avoid wind and handling noise, and use the same orientation. Avoid Bluetooth headsets and call modes that may alter audio.
- We request gain control, echo cancellation and noise suppression off. The browser’s reported settings appear above; hardware processing can still remain.
- The meter stops when this page is hidden. It measures only the active session, not overnight exposure or a full working day.
Why noise belongs in a health conversation
Excessive environmental noise can disturb sleep and is linked to cardiovascular effects, including ischaemic heart disease and hypertension, as well as hearing impairment and tinnitus. WHO explains the health evidence.
A short browser reading cannot establish long-term exposure or diagnose a health problem. For occupational assessments, complaints, hearing-risk decisions or very loud environments, use a calibrated professional instrument and appropriate expert advice.
What do the numbers mean?
dBFS describes captured digital energy relative to full scale. It cannot tell us sound pressure without a reference. After reference adjustment, we show an estimated sound pressure level, rounded to whole decibels to avoid implying precision. The session average uses mean squared samples (energy), not an arithmetic average of decibel readings. Maximum is the highest Fast level, not an impulse peak or certified Lpeak.
How does the meter work?
Audio is processed continuously in an AudioWorklet, rather than sampled occasionally from a screen animation. The A filter uses a bilinear digital approximation of the A-weighting pole/zero model, normalised at 1 kHz. The response differs at high frequencies and the complete microphone/browser system has not been validated against IEC 61672. Unweighted mode removes DC with a 5 Hz high-pass filter; it is not a certified Z-weighted response. Neither mode claims Class 1 or Class 2 accuracy.
All readings and the reference adjustment are temporary. No raw audio, microphone level history or calibration values are sent to our server. Browser microphone permission is required only when you press Start.
Sources
NIOSH: sound level measurement and device limitations · Frequency weighting methods · Browser audio constraints
Updated 6 October 2026. Educational tool; no accuracy tolerance is claimed.