Ovulation, fertility and period calculator
Use our sophisticated ovulation calculator to find out when your most fertile days are and when are you the most likely conceive, based on your menstrual cycle. Simply add the first day of your last period, and let us know the length of your menstrual cycle (it's usually 28 days), and our fertility calculator will show you exactly when are you the most likely to get pregnant.
Your ovulation explained Your details:
Your next ovulation day: 15th of July
- First day of your last period: 1st of July
- Your next period: 1st of July
- Length of your cycle: 28 days
- You should have sex between the 11th of July and 15th of July to conceive a baby.
Now let's take a look at your menstrual cycle and see how we've calculated your ovulation days. You told us that the first day of your last period was on the 1st of July
. Now we'll have to calculate when your next period will happen, and then extract 14 days
from that date, to find out your next ovulation. Here is how we calculated your ovulation days:
- You told us that the first day of your last period was on the 1st of July.
- You also told us that the length of your menstrual cycle is 28 days.
- To find out your next period, we add your menstrual cycle length (28 days) to your last period date (1st of July) - 28 days after the 1st of July is 29th of July.
- Now that we know your next period date, all we have to do is to extract 14 days from that date, to find out your next ovulation date:
- 29th of July minus 14 days will be exactly the 15th of July - this is your next ovulation date, more precisely, this is the day when you'll release an egg, ready to be fertilised
- In order to conceive a baby, it is advised to have sex 5 days before your ovulation date, every day, until your ovulation day - from the 11th of July until the 15th of July.
How women's ovulation date is calculated
This is a break-down of how your ovulation is calculated, and how we work out your most fertile days, based on your menstrual cycle.
When do women ovulate
Your ovulation occurs 14 days before
your next period. Please note: this is
not 14 days after
your last period, but 14 days BEFORE your next period. This is a fairly common misconception, and the fact that most periodic cycles are of 28 days in length, makes many women assume that their ovulation is 14 days after the last period. Obviously, when your cycle length is 28 days, it is actually 14 days after your next period as well (as it's exactly 14 days before the next one), but what happens if your menstrual cycle is 30 days, for example? Well, in this case, you will ovulate 16 days after your last period (which is 14 days before your next one).
- Ovulation occurs 14 days before your next period
- Most periodic cycles are 28 days in length
- Once the egg is released during ovulation, it will live up to 12 hours, waiting to be fertilised
- Sperm can survive up to 5 days in the vaginal tract
- Therefore, you are likely to conceive even if you have sex 5 days before your ovulation day