Period Tracker
Know your cycle – privately
Log the first day of each period. We'll estimate the next one.
Log the day each period starts and we'll estimate when your next one is due, show an approximate fertile window, and work out your average cycle length.
🔒 100% private. Stays on this device only. Nothing is sent anywhere.
🔒 100% private: everything you enter stays on this device only (in your browser's storage). There's no account, nothing is sent to Mildheart or anyone else, and you can delete it all at any time. If you share this device, other people using this browser could see it.
Log a period
Your logged periods
Permanently removes everything saved on this device.
- Logged period
- Predicted period
- Approx. fertile window
- Approx. ovulation
- Today
Your menstrual cycle, simply explained
A period is a natural, healthy part of growing up. A cycle is often around 28 days.
A period is when the lining of the uterus (womb) leaves the body through the vagina. It's a natural, healthy part of growing up. Your cycle is counted from the first day of one period to the day before the next one starts. It's often around 28 days, but anything from about 21 to 35 days is common – and in the first few years after periods start, cycles are often irregular.
1. Period
Usually lasts about 2–7 days. Day 1 of bleeding is day 1 of your cycle – that's the date to log here.
2. Getting ready
After the period, hormones help the lining of the uterus build up again and an egg starts to mature in an ovary.
3. Ovulation
An egg is released, roughly 14 days before the next period. The few days before and including ovulation are when pregnancy is most likely.
4. Before the next period
If the egg isn't fertilised, hormone levels drop and the lining is shed – and a new period begins. Some people feel bloated, moody or crampy in these days.
Learn more: Comic Podcast Ask us
Estimates only. Not medical advice, not contraception. Very painful, very heavy, stopped or suddenly changed periods? Talk to a health worker or a trusted adult.
Please note: this tracker gives estimates only. It is not medical advice and it is not a method of contraception – don't use it to avoid pregnancy. Cycles can change because of stress, illness, growing up and many other things.
If your periods are very painful, very heavy, stop for a long time, or suddenly change, please talk to a health worker or a trusted adult.
