What are Green Days?
Green Days are days that you are not fertile. The algorithm will distribute a Green Day if it has enough data to support that you are not fertile that day, either by confirming that you have already ovulated or that you are unlikely to do so within five days (due to sperm survival).
Since Green Days are your non-fertile days, you can have unprotected sex on Green Days, and you do not need to use additional protection (such as a condom).*
It’s important to note that the fertility status you get each day lasts from midnight to midnight, meaning you’ll get a new fertility status (Red or Green) for each calendar day. If you have sex after midnight, you should first check your new fertility status on the Today page in the NC° app.
When can I start trusting my Green Days?
You can trust your Green Days (including the very first Green Day you get) as long as you see it on the Today view. Please ensure to check your daily fertility status each day before having sex, and do not rely on predictions (as predictions can change when more data is added).
You can learn more about Red and Green Days here, and effectiveness here.
*Remember that the only contraception method that protects against STIs is the male and female condom. Should you have any reason for concern, be sure to use them regardless of fertility status.