Predict your next 12 period dates from your last period start date and average cycle length — with period end dates for each predicted cycle.
Enter your figures and click Calculate to see your results.
Enter your last period start date, your average cycle length and how long your periods typically last.
Press the Calculate button. Results appear instantly using standard clinical and scientific formulas.
Results are displayed with all key values clearly labelled. Use the Copy button to grab your results or Download to save a text file. For health decisions, always consult a healthcare professional.
Yes — completely free with no sign-up required. All calculations run privately in your browser.
Results use standard clinical formulas. For health decisions, always consult a qualified healthcare professional.
Yes — fully responsive and works on all devices.
No — all calculations happen locally in your browser. Nothing is uploaded or stored.
Yes — use the Download button to save a text summary of your results.
