When will I ovulate? Find out with our ovulation calculator

An ovulation calculator can be super helpful if you’re trying to get pregnant. Knowing when you’re ovulating can seem a bit confusing, especially if your periods aren’t regular. To stand your best chance of conceiving, you should try using an ovulation calculator.

It can be a challenging time if you’re struggling to conceive, but try not to worry – they say stress can make it harder to fall pregnant! Instead give yourself the best chance by cluing yourself up with our ovulation calculator.

It’s important to know when the best time to try for a baby is. If you work out when you’re most fertile, you can schedule in some time to get steamy!

An average woman’s menstrual cycle is 28 days but cycles can range from 22 days right up to 36 so don’t just guess. Your menstrual cycle begins on the first day of your period and continues up to the day before you start your next one.

Along with your average menstrual cycle length, you will also need to know the length of your ‘luteal phase’ to use our ovulation calculator as efficiently as possible. The luteal phase begins after ovulation and ends the day before your next period. It usually lasts 12 to 16 days, with an average of 14 days for most women, so if you’re unsure we’d recommend choosing 14 days on the calculator.

As with most ovulation tools, please be aware that the dates given are an estimate and we can’t guarantee they will be 100 per cent accurate. If you conceive outside of your ovulation dates for example, this will impact your due date. Contact you GP or midwife to find out more.

Use our free ovulation calculator to find out when you’re ovulating over the next six months and give yourself the best chance at becoming pregnant – you’re welcome!

Work out your ovulation date using our tool below

Alternatively, follow these three steps to calculate your ovulation date and find out when you’re likely to be most fertile

Step 1: Your menstrual cycle

When your next period starts, make a note of the date. The following month, when your period comes again, make a note of this date, then count the days in between. This will give you your cycle length. You may need to do this for more than one month and take the average, especially if your cycle isn’t regular. Remember also that coming off the Pill will reveal your true menstrual cycle.

Example:
Period starts = 1st January Next period starts = 3rd February
Days in between (including 1st Jan but not 3rd Feb) = 33 days.

Your menstrual cycle length is 33.

Step 2: Your fertile dates


Using our ovulation calender, find the right number in the menstrual cycle length column (33 for the above example) and read across for your ovulation day and most fertile days.

Cycle length Ovulation Most fertile
22 Day 8 Days 7-9
23 Day 9 Days 8-10
24 Day 10 Days 9-11
25 Day 11 Days 10-12
26 Day 12 Days 11-13
27 Day 13 Days 12-14
28 Day 14 Days 13-15
29 Day 15 Days 14-16
30 Day 16 Days 15-17
31 Day 17 Days 16-18
32 Day 18 Days 17-19
33 Day 19 Days 18-20
34 Day 20 Days 19-21
35 Day 21 Days 20-22
36 Day 22 Days 21-23

Step 3: Your ovulation date

Work out your ovulation and most fertile dates. For the below example:

First day of last period = 3rd February 2008
Cycle Length = 33
Ovulation (19 days later) = 22nd February 2008
Most fertile (18-20 days later) = 21st and 23rd February 2008

Once you know your ovulation date, as a rule, you are most fertile the day before, during and the day after. It makes sense to try and have as much sex as you can at those times, and to improve your chances even more you can test some of our hottest sex positions for getting pregnant. Because sperm can survive for up to seven days in the right conditions you could be fertile before and after these days, which you guessed it – means even more sex!

N.B These figures are based on averages and should be used as a guide only. Days and dates may differ from woman to woman.