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Legal

Privacy Policy

Last updated: 6 October 2026. This policy explains what data we collect, how we use it, and your rights.

Plain English summary: We collect minimal data. We never sell your data. Calculator inputs never leave your device. You can ask us to delete your data at any time.

Who We Are

BedtimeSleepCalculator.com is a free online sleep science tool. Contact: hello@bedtimesleepcalculator.com

What Data We Collect

Data you provide directly

If you email us, including through the contact page, we receive your email address and anything you include. We use it only to reply to you. We do not currently run an email newsletter.

Calculator usage data

All calculations happen entirely in your browser. We do not collect or store the bedtimes or alarm times you enter. This data never leaves your device.

Analytics and cookies

We use Google Analytics to understand aggregate site usage. We use local storage to remember your theme preference (dark or light mode). Affiliate tracking cookies may be set by third party platforms when you click product links.

Advertising

This site shows ads served by Google AdSense. Google and its partners may use cookies or similar technologies to serve ads based on your visits to this and other websites. You can learn how Google uses this information at policies.google.com/technologies/partner-sites and manage personalised ads at adssettings.google.com.

Weather data on city pages

City pages request weather data from Open Meteo directly from your browser, which means Open Meteo receives your IP address as part of that request.

How We Use Your Data

To operate and improve the website and calculator tools
To respond to your enquiries and support requests
To analyse aggregate usage patterns and improve our content
To comply with legal obligations

We do not sell, rent, or share your personal data with third parties for marketing purposes.

Third Party Services

Google Analytics (aggregate analytics); Google AdSense (advertising); Open Meteo (weather data on city pages); Amazon Associates and affiliate platforms (purchase tracking via product links).

Your Rights

You have rights to access, correct, delete, or export your personal data. Email hello@bedtimesleepcalculator.com to exercise any right. We respond within 30 days.

Children

We do not knowingly collect data from children under 13. Contact us immediately if you believe this has occurred.

Changes

We may update this policy. Material changes will be announced on the website. Continued use after a policy update constitutes acceptance.