Terms of Service

Effective: May 6, 2026

1. Acceptance of Terms

By accessing or using rundida.com ("RunDida", "we", "us", "our"), you agree to be bound by these Terms of Service. If you disagree with any part, please do not use the service.

2. Service Description

RunDida is a free running tools platform offering 97 calculators, educational guides, marathon detail pages, training plans, a public JSON API, and an MCP server for AI agents. All core tools are free and require no signup. We support three languages: English, Chinese (中文), and Japanese (日本語).

3. User Responsibilities

By using RunDida, you agree to:

  • Treat tool results as informational only. The calculators are estimates, not medical or training advice. Consult a qualified coach or physician before changing your training, especially if you have a medical condition.
  • Use the public JSON API responsibly. Reasonable use is unmetered; sustained automated scraping may result in rate limiting or blocking. Please contact us if you have a legitimate high-throughput use case.
  • Not attempt to circumvent any security measures, scrape non-public data, or reverse-engineer the platform.
  • Not use RunDida to harm yourself or others.

4. Third-party Services

RunDida integrates the following third-party services. Their data practices are governed by their own privacy policies (linked from our Privacy Policy):

  • Google AdSense — display advertising
  • Google Analytics — anonymized traffic analysis
  • Google Search Console — SEO data
  • OpenWeatherMap — weather data for marathon countdown and weather-related tools
  • Affiliate networks — we may use providers such as Awin, Impact, Avelon, Booking.com, and Amazon Associates

5. Disclaimer

Tool results are calculated using established sport science formulas (Daniels, Karvonen, Cooper, Riegel). All formulas are documented on our methodology page. Results represent estimates, and individual variation exists. RunDida does not guarantee the accuracy, completeness, or fitness for any particular purpose of any tool output. Use at your own risk.

The marathon information we provide (course details, weather history, race-day strategy) is compiled from public sources. Always verify race details on the official race website before registering or traveling.

6. Limitation of Liability

To the maximum extent permitted by law, RunDida and its operators are not liable for any direct, indirect, incidental, consequential, or punitive damages arising from use of the service, including but not limited to:

  • Training injuries or health issues
  • Race-day decisions based on tool outputs
  • Travel and lodging decisions made for marathon trips
  • Any financial decisions made based on the platform

7. Affiliate Disclosure

RunDida includes affiliate links on certain pages. All affiliate links are marked with rel="sponsored" as required by Google. When you click an affiliate link and complete a purchase, we may receive a commission at no additional cost to you. This does not affect our content or recommendations — we only recommend products and services we genuinely believe are useful for runners.

8. Intellectual Property

All content on RunDida (calculators, guides, marathon pages, original images) is © 2025-2026 RunDida unless otherwise noted. Our public JSON API may be used freely under fair-use terms; please credit "rundida.com" if you republish or build on our data. Our MCP server (@rundida/mcp-server) is MIT-licensed.

9. Changes to Terms

We reserve the right to modify these Terms at any time. Material changes will be reflected in the "Effective" date above. Your continued use of the service after changes constitutes acceptance.

10. Contact & Governing Law

For questions about these Terms, contact our team or email support [at] rundida.com.

These Terms are governed by the laws of the People's Republic of China. Any disputes will be resolved in the competent courts of Shanghai, PRC.