Clue helps everyone with a menstrual cycle understand their body using a science-based, privacy-first mobile app. We provide accurate period, ovulation and fertility predictions, symptom tracking, and personalized insights to support menstrual, reproductive, and sexual health.

We deliver trustworthy information, data‑driven tools, and emotional support from first period to last. Products include the free Clue app, premium Clue Plus, educational content on helloclue.com, research partnerships, and clinical-grade features — all designed to be evidence-based and user-friendly.

Clue is committed to strict EU/German data privacy: we do not sell users’ health data. Our real-world dataset supports academic research in partnership with institutions like Oxford, Berkeley and MIT. Millions of people in 190+ countries use Clue; the app is available in 20+ languages.