Find your most fertile days and best window to conceive, based on your cycle length and last period. Free, private and instant.
Sperm can live up to 5 days — the fertile window is wider than most people think.
See your next cycle's key dates instantly and plan accordingly.
All calculations run locally in your browser. Nothing is sent anywhere.
Results update as you type. No buttons, no reloads.
Track your cycle, pregnancy and wellness with confidence.