Where are you in your cycle?
See where today falls in your calculated cycle. The ring and phase band put the date ranges in context. They use your inputs, not measurements.
Your cycle takes shape here
Enter your last period start in the form. Your calculated date ranges will appear here.
This ring is only an example of a 28-day cycle.
Your inputs stay when you switch views. Opening a new page starts with empty inputs. Open this view on its own page
An orientation based on your inputs
The calculator repeats your cycle length. If your last period started further back, it shows the calculated cycle that contains today. It does not detect actual bleeding or phases. The results are not suitable for contraception, diagnosis or identifying ovulation.
Good to know
What does the phase shown for today mean?
It is the phase into which today falls in the calculation model. The calculator counts from your period start and repeats your cycle length. It does not measure hormones or detect your actual phase.
How does the model divide the four phases?
For a 28-day cycle with a 14-day luteal phase, the model uses 5 days of menstruation, 6 follicular days, 3 ovulatory days and 14 luteal days. Different inputs change this breakdown. This is a calculation model, not evidence of ovulation.
Why do my two lengths not fit together?
The other phases need at least 8 days in total within this model. An 18-day luteal phase, for example, does not fit into a 20-day cycle. Check both inputs; the error message is not a judgement about your body.
What does the dot on the ring mean?
The dark dot marks today’s calculated cycle day. The phase band shows the breakdown across the full cycle. All date ranges, cycle days and durations are also written out below it.
Follow your phases day by day in the BodySeasons app
In the app you record how you actually feel and recognise your own patterns across weeks and cycles. No points, no streaks, no grading.
Explore BodySeasons