Cycle calendar: calculate period, ovulation & fertile days

Zuletzt aktualisiert am 29.08.2026

Was Du auf dieser Seite findest:

Your online cycle calendar
What is a cycle calendar?
What is a cycle calendar useful for?
Cycle calendar as an app

Your online cycle calendar

Use our online calculator here conveniently to find out the following:

Your period
Fertile days
Likely ovulation

Periodenrechner

Tag 1 Deiner letzten Periode

Zykluslänge in Tagen

Please note: the result is only an estimate based on the data you entered. Every cycle is individual and can therefore differ from the calculated result.

Stay tuned and track your cycle regularly…

… with the cycle app from cyclotest. Forecasts and cycle diary in one.

Use the cyclotest app for free

What is a cycle calendar?

First and foremost, a cycle calendar is a completely normal calendar in which you enter the start and end of your period. If you keep these entries over several months, you can calculate your average cycle length, because it is not always 28 days.

Cycle calendars exist in three different forms:

as a printable paper version
as an app
as an online calculator

The way they work is similar. The only difference: the app and the online calculator do the calculation for you. In paper form, you have to do it yourself.

Even though many cycle apps on the market advertise that they can calculate your ovulation, this is not possible. Neither cycle calendars nor simple ovulation calculators can predict a woman’s ovulation. The release of the egg cell can be influenced by various factors, so the cycle day can vary and average values are not really helpful here.

What is a cycle calendar useful for?

A cycle calendar has several advantages. On the one hand, you get to know your cycle better; on the other hand, the forecasts help you plan appointments better. Your gynecologist will also be pleased if you bring your cycle calendar to your next appointment. Are you planning a pregnancy? With the help of the calendar, you know from when you can take a pregnancy test, i.e. when your next period would be due.

A cycle calendar is not suitable for contraception or for trying to conceive, because it only represents the simple calendar method, which is very unreliable. Instead, you can use the more reliable methods of natural family planning, such as the symptothermal method, and use them to calculate your
fertile days individually.

Cycle calendar as an app

In addition to the large selection of printable cycle calendars and online calculators, there are numerous apps. Many differ only in their design. The cyclotest mySense app also offers a cycle calendar. Good to know: it is a certified medical device.

Try the cyclotest mySense app for free now

cyclotest mySense: cycle calendar included

In the mySense app, you can view past cycles or forecasts for the following 12 months that tell you when your next bleeding should occur.

cyclotest mySense – calendar view

As with a printable cycle calendar, you first record your bleeding. You can also enter the intensity at the same time.

cyclotest mySense also as a cycle diary

But that is only the beginning. Learn more about your body by additionally tracking ovulation symptoms and other observations, so you can possibly recognize certain patterns & connections.