Introduction
Welcome to the Period Calculator website ("we," "us," or "our"). We are committed to protecting the privacy and security of our visitors and users. This Privacy Policy explains our data collection, processing, and storage practices. It applies specifically to the operations of our Free Period Calculator tool and the associated pages on this website.
We understand that information about your menstrual cycles, fertility, and reproductive health is highly personal. Because of this, we designed our platform to operate with a "local-first" approach. This means that calculations are performed directly on your device, and your private data never leaves your browser.
1. Information We Collect
We do not collect, store, or share your personal health information. When you use our period calculator, you enter parameters such as the start date of your last period, your typical cycle length, and the duration of your bleeding. This data is processed locally by your browser's JavaScript engine to display predictions. We do not transmit these inputs to our servers, nor do we save them in external databases.
When you use our website, we may collect minimal technical data that does not identify you. This includes:
- Device Information: Operating system, browser type, version, and screen resolution.
- Usage Data: Pages visited, time spent, reference pages, and general navigation flow.
- IP Addresses: Used briefly for network security and general location statistics (such as country level), but not linked to your calculator entries.
If you contact us using our contact form, we collect the details you provide: your name, email address, subject, and message content. We use this information solely to respond to your request, and we do not share it with third parties.
2. Cookies and Local Storage
We use cookies and local storage to improve your browsing experience and keep our website functional.
Cookies: These are small text files stored on your device by your browser. We may use temporary session cookies to manage site settings, navigation flow, and to secure contact form submissions. You can set your browser to refuse cookies or alert you when they are sent, though some parts of the site may not function properly without them.
Local Storage: Our calculator may use the browser's Web Storage API (specifically `localStorage`) if you choose to save your inputs for future visits. This allows the tool to remember your cycle length and last period date so you don't have to enter them again. This data remains on your device, and you can clear it at any time by clearing your browser cache or resetting the calculator.
3. Analytics Services
To understand how visitors use our site and to improve its performance, we may use basic, privacy-focused analytics tools (such as anonymized self-hosted analytics or Google Analytics with IP anonymization enabled).
These services collect aggregate data, such as total page views, bounce rates, and traffic sources. They do not track your individual calculator entries or associate your browsing behavior with your identity. The aggregate information is used to optimize the site layout, speed, and usability.
4. Third-Party Services and CDNs
To deliver a fast, responsive, and visually consistent user experience, our website loads certain resources from Content Delivery Networks (CDNs).
Specifically, we load typography styles from Google Fonts and icons from Font Awesome. When your browser requests these resources, the CDN providers may receive basic technical data, such as your IP address and user-agent details. These providers handle your data in accordance with their own privacy policies. We do not use third-party tracking services or host advertising networks that track you across different websites.
5. Data Usage and Processing
Any data processed by our website is used strictly to provide the calculations you request:
- Calculations: Cycle and ovulation prediction inputs are processed immediately to display results and are not stored.
- Inquiries: Information submitted via the contact form is used only to answer your questions and is deleted once resolved.
- Newsletters: If you sign up for our newsletter, we use your email address only to send updates. We do not sell or rent our email list to third parties, and you can unsubscribe at any time.
6. Data Security Measures
We use standard technical and organizational measures to protect our website and users:
All traffic between your device and our servers is encrypted using Transport Layer Security (TLS) and HTTPS. This prevents interception of information during transmission. Since we do not store health data on our servers, there is no risk of a server-side database breach exposing your personal cycle details. We advise you to protect your device with passwords and use secure web browsers to keep your local data safe.
7. User Rights and Compliance
Depending on your location, you may have rights under laws like the General Data Protection Regulation (GDPR) in the European Union or the California Consumer Privacy Act (CCPA).
Because we do not store personal health data, we do not maintain records that can be modified or deleted. However, you have complete control over the data processed by our site:
- Access and Correction: You can view, modify, or delete your inputs at any time by changing the fields in the calculator or using the reset button.
- Erasure: You can clear all locally saved data by clearing your browser's local storage and cache.
- Opt-Out: You can disable cookies and local storage in your browser settings to prevent any local data retention.
8. Contact Information
If you have questions about this Privacy Policy or how we handle data on our website, please contact our privacy coordinator:
Email: privacy@periodcalculator.com
Address: Period Calculator Privacy Office, 120 Health Sciences Blvd, Suite 400, Boston, MA 02111
9. Policy Updates
We may update this Privacy Policy from time to time to reflect changes in our services or legal requirements. When we make updates, we will post the revised version on this page with the update date. We encourage you to review this page periodically to stay informed about our privacy practices.
Last updated: July 3, 2026