Privacy Policy

Last updated: 2026-05-01

Sound Decibel Meter is operated at sounddecibelmeter.org (the "Site"). This page explains, in plain language, what data we handle, what we don't, and how the Site is built so you can verify it.

The summary fits in three lines:

• Microphone audio never leaves your device. All sound analysis is done locally in your browser; we have no audio endpoint and no audio storage.
• No account is required, ever. We do not ask for an email, name, or password.
• We use minimal, aggregated analytics on the article pages only. No fingerprinting, no advertising trackers, no third-party data brokers.

The rest of this page is the long version, organised by category of data.

What we collect

Microphone audio

We collect none. The browser sound meter on the home page requests microphone access via the standard getUserMedia API and processes the audio stream locally through the Web Audio API. The resulting decibel values are rendered on screen and discarded. No audio samples, FFT frames, derived levels, or any other audio-adjacent data are ever transmitted to a server. The Site has no audio analysis endpoint because there is no server-side audio processing whatsoever.

You can verify this for yourself: open your browser's network panel during a measurement session and watch the traffic. You will see no requests after the page loads.

When you close the tab, the microphone is released automatically.

Local browser storage

The Site uses your browser's localStorage to persist three small preferences across visits:

• Calibration offset (a single signed dB value) — so you don't have to recalibrate every session.
• Theme (light or dark).
• Language (one of the supported locales).

This data lives only on your device, scoped to the sounddecibelmeter.org origin. It is never transmitted to us. Clearing your browser's site data removes it.

Analytics

On the article pages (everything except the meter on the home page), we use a privacy-respecting analytics service to count aggregate visits. The fields we receive are:

• Page URL (e.g., /calibration).
• Referrer (the previous page you came from).
• Approximate country (derived from IP at request time, then discarded).
• Browser type and screen size (broad bucket).
• Whether the visit is a first-time or returning view.

We do not receive your IP address, device fingerprint, login state, or any identifier that would let us follow you across sites. The Site does not load advertising trackers, cross-site cookies, or social media pixels.

We deliberately do not run analytics during a meter session on the home page, so meter use leaves no trace beyond the session itself.

Cookies

The Site sets one technical cookie used by the language router (NEXT_LOCALE) to remember your preferred locale. There are no advertising or tracking cookies.

If your jurisdiction requires explicit cookie consent for analytics (EEA, UK, Switzerland, others), you can disable analytics in your browser's "Do Not Track" settings, via a content blocker, or by declining consent in the prompt your browser shows the first time it loads an analytics script. The meter itself works the same in either case.

Affiliate links

A small number of articles link to consumer hearing-protection products on third-party retailers (e.g., Amazon). Some of those links carry an affiliate tag — meaning the retailer pays us a small commission if you buy after clicking. This is the only commercial relationship the Site has. The affiliate retailer sees the click and may set their own cookies after you arrive on their domain; that data is governed by their privacy policy, not ours.

We label affiliate links inline where they appear and never let commercial considerations alter the technical recommendations we publish.

Email

If you contact us at the address listed on the Contact page, we receive your email address and the message you send. We use it to reply, retain it for as long as needed to provide ongoing support, and then delete it. We do not add you to any mailing list and we do not share your address with third parties.

What we do not collect

To make this exhaustive:

• We do not record, store, transcribe, or analyse audio from your microphone.
• We do not read or write files on your device beyond localStorage as described above.
• We do not collect health information, even though the Site discusses hearing health.
• We do not collect location data beyond approximate country for analytics.
• We do not run advertising networks, social-media trackers, retargeting pixels, or session replay tools.
• We do not sell, rent, or share data with data brokers.

Children

The Site is intended for a general audience. We do not knowingly collect personal information from anyone under 13, and the meter itself is designed not to collect personal information from anyone of any age. Parents who notice anything that contradicts this can write to us and we will investigate.

International transfers

We are based in a single country and our analytics provider may store aggregate logs in a country different from yours. Because we do not collect personal data tied to identified individuals, this transfer carries minimal privacy risk. If you are an EEA, UK, or Swiss resident exercising rights under the GDPR or equivalent, see Your rights below.

Your rights

If you are in a jurisdiction with a comprehensive privacy law (EEA, UK, California, Brazil, others), you have rights of access, correction, deletion, portability, and objection. Because the Site holds essentially no personal data about you — no account, no audio, no profile — most of these rights resolve to "there is nothing to deliver or delete." If you have specifically emailed us and want your prior correspondence deleted, write to the contact address and we will action it within 30 days.

The Site is not currently subject to a data protection authority register, since the categories of data we process do not require one. If a data protection regulator wishes to contact us, the contact email reaches a human within one business day.

Changes to this policy

If we change anything material, we will update the "Last updated" date at the top of this page and post a brief note on the home page for at least 30 days. Cosmetic edits (typos, link reformatting) are made without notice.

Contact

Questions about this policy or the data the Site handles: see the Contact page. Plain English answers preferred, plain English answers given.