Introduction
Negative Split Calculator ("we", "us", or "our") operates the negative-split.run website. This page informs you of our policies regarding the collection, use, and disclosure of personal information when you use our service.
Information We Collect
Authentication Data
When you sign in using one of our supported authentication providers (Google, Facebook, Apple, Strava, or Garmin), we collect:
- Your email address
- Your name
- Your profile picture/avatar (if provided by the auth provider)
- Authentication provider identifier
Usage Analytics
We use PostHog analytics to understand how our service is used. This may include:
- Pages visited and features used
- Time spent on the site
- Device and browser information
- General location (country/city level)
- Interactions with calculator settings (distance, unit, split percentage)
- File download events
Calculator Preferences
Your calculator settings (race distance, target time, negative split percentage, unit preference) are processed in your browser and are not stored on our servers unless you are authenticated.
How We Use Your Information
We use the collected information for:
- Providing and maintaining our service
- Authenticating your identity
- Generating personalized workout files (FIT format)
- Improving user experience and service functionality
- Understanding usage patterns and improving features
- Communicating important updates (if necessary)
Data Storage and Security
Your authentication data is securely stored using Supabase, a SOC 2 Type II certified platform. We implement appropriate technical and organizational security measures to protect your personal information against unauthorized access, alteration, disclosure, or destruction.
Analytics data is processed and stored by PostHog in accordance with their privacy policies.
Third-Party Services
We use the following third-party services:
- Supabase - Authentication and database services
- PostHog - Product analytics and user behavior tracking
- OAuth Providers - Google, Facebook, Apple, Strava, and Garmin for authentication
- Vercel - Hosting and content delivery
Each service has its own privacy policy governing the use of your data. We encourage you to review their privacy policies.
Cookies and Local Storage
We use cookies and browser local storage to maintain your authentication session and remember your preferences. These are essential for the service to function properly.
Data Retention
We retain your personal information only for as long as necessary to provide you with our service and as described in this privacy policy. You may request deletion of your account and associated data at any time.
Your Rights
You have the right to:
- Access your personal data
- Correct inaccurate data
- Request deletion of your data
- Object to processing of your data
- Export your data
- Withdraw consent at any time
To exercise any of these rights, please sign out and delete your account, or contact us for assistance.
Children's Privacy
Our service is not directed to individuals under the age of 13. We do not knowingly collect personal information from children under 13. If you become aware that a child has provided us with personal information, please contact us.
International Data Transfers
Your information may be transferred to and maintained on servers located outside of your jurisdiction where data protection laws may differ. By using our service, you consent to this transfer.
Changes to This Privacy Policy
We may update our privacy policy from time to time. We will notify you of any changes by posting the new privacy policy on this page and updating the "Last updated" date at the top of this policy.
GDPR Compliance
If you are a resident of the European Economic Area (EEA), we process your data in accordance with the General Data Protection Regulation (GDPR). Our legal basis for processing is your consent when you sign in to use our service.
California Privacy Rights
If you are a California resident, you have specific rights under the California Consumer Privacy Act (CCPA). We do not sell your personal information. You have the right to request disclosure of the categories and specific pieces of personal information we have collected.
Contact Us
If you have any questions about this privacy policy or our data practices, please contact us through the authentication provider you used to sign in, or create an issue on our support channels.