How does Natural Cycles work?

Backed by science, the NC° algorithm is powered by body temperature.
Woman holding up natural cycles app

How to use Natural Cycles

Measure your temperature


Choose your device and measure either overnight or in the morning.

Open the NC° app

woman looking at her data with Natural Cycles

The algorithm behind the app is analyzing your body temperature.

Confirm your fertility status

Woman holding Natural Cycles app in her hands

At a glance, know if today is a Green Day (not fertile) or a Red Day (use protection).

Body temperature and the cycle

Our hormones cause body temperature to rise around ovulation. By analyzing this we can pinpoint where you are in your cycle.

A method that’s tailored to you

Not only can we confirm ovulation but we can predict it, based on your unique cycle.

看看algorithm works:

visualisation of a menstrual cycle with period and ovulation marked

Your cycle starts on the first day of your period. Most of us aren’t fertile at this time so you will get Green Days.

Inside the NC° app

Natural Cycles app screen showing the fertility status for the day which reads Not Fertile.

View your fertility status

It's easy to see if today is a Green or Red Day so you know if you need to use protection.

Natural Cycles add data

Track and learn more

Monitor emotional and physical symptoms to learn about the changes in your body.

demo of information on app

See the bigger picture

Spot patterns and compare previous cycles with your graph view.

Natural Cycles app showing the settings screen where the user can change the app's mode.

Adapt your fertility journey

Smoothly switch between preventing or planning pregnancy at no extra cost.

Read more about NC° Birth Control Read more about NC° Plan Pregnancy

Go hormone-free today