Period Calculator
Predict your next few periods and ovulation day based on your last period and average cycle length.
Show solution steps
What is the Period Calculator?
A period calculator estimates when your next period is due and when you ovulate, based on your cycle length. Useful for tracking and planning.
How to Calculate
The next period is your last start date plus your cycle length; ovulation is estimated about 14 days before the next period.
Formula
Next period = last period + cycle length
How to Use
- Enter your details in the fields above.
- The result updates instantly as you type.
- Use Copy, Print or Download PDF to save your result.
Frequently Asked Questions
How accurate is this?
It's an estimate based on a regular cycle. Cycles vary naturally, so treat the dates as a guide, not a guarantee.
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