ToolnozaHEALTH TOOL
Period Calculator — Next Cycle Dates
Estimate the next three period start dates from your usual cycle length.
Period Calculator — Next Cycle Dates
FREE ONLINE TOOLSTEP BY STEP
How to use period calculator — next cycle dates
- Enter the labelled values in the displayed units.
- Review the method: Estimated start of cycle n = last recorded start + n × usual cycle length. Bleeding end = estimated start + duration − 1 day.
- Read the worked example and method limitations.
WHEN IT HELPS
Common uses
- Compare the assumptions: Starting 1 October 2026, a 28-day cycle and 5 days of bleeding give a next estimated period of 29 October–2 November.
IN PRACTICE
Example
Starting 1 October 2026, a 28-day cycle and 5 days of bleeding give a next estimated period of 29 October–2 November.
GOOD TO KNOW
Can this detect pregnancy or a cycle disorder?
No. It repeats your entered cycle length and cannot explain late or missed periods. Predictions become less reliable when cycles vary. It is not contraception or a diagnostic test.
Frequently asked questions
Can this detect pregnancy or a cycle disorder?
No. It repeats your entered cycle length and cannot explain late or missed periods. Predictions become less reliable when cycles vary. It is not contraception or a diagnostic test.
Which formula is used?
Estimated start of cycle n = last recorded start + n × usual cycle length. Bleeding end = estimated start + duration − 1 day.