Privacy Policy
Last updated: March 2025
1. Introduction
Welcome to Sleep Cycle Optimizer (also known as "Best Bedtime Calculator"), accessible at best-bedtime-calculator.vercel.app. We are committed to protecting your privacy and ensuring transparency in how we handle any data associated with your use of our web application.
This Privacy Policy explains what information we collect when you visit and interact with our sleep cycle calculator, how that information is used, and the choices you have regarding your data. By using our website, you acknowledge that you have read and understood the practices described in this policy. If you do not agree with any part of this policy, we encourage you to discontinue use of the application.
Our calculator is designed to help you determine optimal bedtimes and wake-up times based on 90-minute sleep cycles. The tool operates primarily in your browser, and we have designed it to minimize the amount of personal data we collect. We do not require you to create an account, provide your name, email address, or any other personally identifiable information (PII) to use the core features of this application.
2. Information We Collect
We collect limited, mostly anonymous information to improve our service and understand how visitors use the application. The categories of data we collect are outlined below.
2.1 Usage Data
When you interact with our sleep cycle calculator, we may collect anonymous usage data including:
- Wake-up times entered: The times you input into the calculator when determining your ideal bedtime or sleep schedule. These values are not linked to any personally identifiable information.
- Calculator mode used: Whether you use the "I need to wake up at..." mode, the "I want to go to sleep at..." mode, or the "I want to sleep/nap now" mode. This helps us understand which features are most popular.
- Interaction patterns: General information about how you interact with the interface, such as which buttons are clicked and which results are viewed.
2.2 Data Sent via Webhook
Certain anonymous usage data may be transmitted to Google Sheets via a webhook endpoint for aggregate analytics purposes. This data is strictly anonymous and contains no personally identifiable information (PII). The information sent may include timestamps of visits, calculator modes selected, and general usage statistics. This data is used exclusively for understanding overall usage patterns and improving the application.
2.3 Browser Information
We may collect standard browser information that is automatically transmitted when you visit any website, including:
- User agent string: This includes your browser type, version, and operating system. We use this for analytics and to ensure compatibility across different browsers and devices.
- Screen resolution and viewport size: Used to understand how users experience the application on various devices.
- Referring URL: The web address that directed you to our site, if applicable.
2.4 Local Storage Data
Our application uses your browser's local storage (a client-side storage mechanism similar to cookies) to save your preferences and improve your experience. The following data is stored locally on your device and is never transmitted to our servers:
- Theme preference: Whether you prefer the dark or light theme, stored under the key
theme. - Sleep latency setting: Your custom sleep latency (the time it takes you to fall asleep), so you do not need to re-enter it on each visit.
- Last wake time: The most recent wake-up time you entered, for convenience on return visits.
You can clear this data at any time by clearing your browser's local storage or site data for our domain.
2.5 Session Storage
We use session storage (which is automatically cleared when you close your browser tab) for temporary data such as:
- Visitor counting: A session flag to track whether you have been counted as a visitor for the current session, ensuring accurate daily visitor statistics without double-counting.
Session storage data exists only for the duration of your browser session and is never persisted or transmitted externally.
4. Advertising
We use third-party advertising networks to display ads on our website. These networks help us keep the Sleep Cycle Optimizer free for all users. Our advertising partners include:
- Google AdSense: Google uses cookies (including the DoubleClick cookie) to serve ads based on your prior visits to our website and other sites on the internet. Google's use of advertising cookies enables it and its partners to serve ads to you based on your browsing patterns.
- Adsterra: Adsterra is an advertising network that may use cookies and similar technologies to deliver targeted advertisements. Adsterra collects and processes data in accordance with its own privacy policy.
How to Opt Out of Personalized Advertising
You have several options to control or opt out of personalized advertising:
- Google Ad Settings: Visit Google Ads Settings to manage your ad personalization preferences or opt out entirely.
- NAI Opt-Out: Visit the Network Advertising Initiative opt-out page to opt out of targeted advertising from participating ad networks.
- DAA Opt-Out: Visit the Digital Advertising Alliance opt-out page for additional choices.
- Browser settings: Most modern browsers allow you to block third-party cookies or use "Do Not Track" signals. Consult your browser's help documentation for instructions.
- Cookie consent banner: When presented with our cookie consent banner, selecting "Decline" will prevent non-essential third-party cookies from being set.
Please note that opting out of personalized advertising does not mean you will no longer see ads. You will still see advertisements, but they may be less relevant to your interests.
5. How We Use Your Information
The limited information we collect is used for the following purposes:
- Providing and improving the service: Usage data helps us understand which features are most valuable and where improvements can be made to the sleep cycle calculator.
- Personalizing your experience: Local storage data ensures your preferred theme, sleep latency, and other settings persist between visits.
- Aggregate analytics: Anonymous data sent via webhooks to Google Sheets helps us track overall usage trends, such as peak usage hours and popular calculator modes.
- Advertising: Third-party advertising partners use cookies to serve relevant advertisements that fund the continued operation of this free tool.
- Technical troubleshooting: Browser information helps us identify and fix compatibility issues across different devices and browsers.
We do not use your data to build personal profiles, sell individual user data, or contact you in any way.
6. Data Sharing and Third Parties
We do not sell, rent, or trade your personal information. However, certain anonymous data may be shared with or accessible to the following third parties as part of the normal operation of our website:
- Google (AdSense and Analytics): Anonymous usage and advertising data as described in the sections above.
- Adsterra: Advertising-related data for the purpose of serving and measuring advertisements.
- Google Sheets (via webhook): Anonymous, aggregate usage statistics for our internal analytics purposes.
- Vercel: Our hosting provider, which may process standard server logs including IP addresses and request metadata as part of delivering the website to your browser. Please review Vercel's Privacy Policy for details.
- Plausible Analytics: If enabled, Plausible processes anonymous, aggregate analytics data without using cookies or collecting personal information.
We may also disclose information if required by law, regulation, or legal process, or if we believe in good faith that disclosure is necessary to protect our rights, your safety, or the safety of others.
7. Data Security
We take the security of your data seriously and implement appropriate technical measures to protect the information associated with your use of our service:
- HTTPS encryption: All data transmitted between your browser and our servers is encrypted using TLS (Transport Layer Security), ensuring that information cannot be intercepted in transit.
- Minimal data collection: By design, we collect as little data as possible. The majority of your settings and preferences are stored locally in your browser and never leave your device.
- No account system: Since we do not require user accounts, there are no passwords, email addresses, or personal profiles that could be compromised.
- Third-party security: Our hosting provider (Vercel) and third-party services employ their own robust security measures. We encourage you to review their respective security practices.
While we strive to protect your information, no method of electronic transmission or storage is 100% secure. We cannot guarantee absolute security, but we are committed to implementing and maintaining reasonable safeguards.
8. Children's Privacy
Our website is intended for a general audience and is not directed at children under the age of 13. We comply with the Children's Online Privacy Protection Act (COPPA) and do not knowingly collect personal information from children under 13 years of age.
Since our application does not require account creation or the submission of any personally identifiable information, the risk of inadvertently collecting children's data is minimal. However, third-party advertising networks that display ads on our site may use cookies, and we encourage parents and guardians to monitor their children's internet usage.
If you believe that we have inadvertently collected information from a child under 13, please contact us immediately at the address provided below, and we will take prompt steps to delete such information.
9. Your Rights
Depending on your location, you may have specific rights regarding your data under applicable privacy laws.
European Economic Area (GDPR)
If you are located in the European Economic Area (EEA), you have the following rights under the General Data Protection Regulation (GDPR):
- Right of access: You can request information about the data we hold related to your use of our service.
- Right to rectification: You can request correction of any inaccurate data.
- Right to erasure: You can request that we delete data associated with you.
- Right to restrict processing: You can request that we limit how your data is processed.
- Right to data portability: You can request a copy of your data in a structured, machine-readable format.
- Right to object: You can object to the processing of your data for certain purposes, including direct marketing.
Since we do not collect personally identifiable information, most of these rights are satisfied by default. You can clear all locally stored data by clearing your browser's site data for our domain at any time.
California (CCPA)
If you are a California resident, the California Consumer Privacy Act (CCPA) provides you with additional rights:
- Right to know: You can request that we disclose what personal information we collect, use, and share.
- Right to delete: You can request deletion of your personal information.
- Right to opt out of sale: You can opt out of the sale of your personal information. We do not sell personal information as defined by the CCPA.
- Right to non-discrimination: We will not discriminate against you for exercising your CCPA rights.
To exercise any of these rights, please contact us using the information provided in Section 11 below.
10. Changes to This Policy
We may update this Privacy Policy from time to time to reflect changes in our practices, technology, legal requirements, or other factors. When we make material changes to this policy, we will update the "Last updated" date at the top of this page.
We encourage you to review this Privacy Policy periodically to stay informed about how we are protecting your data. Your continued use of the Sleep Cycle Optimizer after any changes to this policy constitutes your acceptance of the updated terms.
If we make significant changes that materially affect how we handle previously collected data, we will make reasonable efforts to notify users through a visible notice on our website.
11. Contact Information
If you have any questions, concerns, or requests regarding this Privacy Policy or our data practices, please contact us at:
Email: privacy@bestbedtimecalculator.com
We will respond to your inquiry within a reasonable timeframe. For GDPR-related requests, we will respond within 30 days as required by applicable law. For CCPA-related requests, we will respond within 45 days.