About

Why this site exists

Sound Decibel Meter is a free sound level meter that runs in your phone or computer browser. It measures how loud a place is in decibels (dB) and explains what the numbers mean. Use it to compare rooms, find loud hours, or check a sound against public health guidelines.

The meter shows live levels and averages. The guides explain the decibel scale, typical sound levels, and public health limits in plain language.

What the site does

• Measures sound level with your device's microphone, in dBA (the default) or dBC.
• Shows the live level, Min, Avg (Leq), and Max, with a graph of the last 60 seconds.
• Keeps a noise log for hours at a time, storing one level per second.
• Accepts a Calibration Offset if you have a reference meter to compare against.
• Explains each level from 10 to 140 dB on its own page.

What the site does not do

• It does not record or upload audio.
• It does not ask for an account or an install.
• It does not produce certified or legal measurements.
• It does not support external microphones yet.

How accurate it is

A phone is not a calibrated sound level meter. No phone app meets the IEC 61672 Class 1 or Class 2 standard on its own. Built-in microphones are made for voices, have a noise floor of roughly 25 to 35 dB, and reach a ceiling around 95 to 110 dB.

Treat readings as estimates. They are most useful for comparing rooms or times on the same device, in the same spot.

How your data is handled

The meter analyzes the microphone signal on your device. Audio is never uploaded or recorded. Your settings and noise logs stay in your browser.

Where the guidance comes from

The limits and guidelines come from public bodies: NIOSH, the US National Institute for Occupational Safety and Health; OSHA, US workplace law; the WHO, the World Health Organization; and the CDC, the Centers for Disease Control and Prevention.

Contact

For questions or problems, use the contact form. The site does not publish a phone number, street address, or company name.