Ovulation calculator

Each woman's menstrual cycle is different, so getting to know your body better can improve your chances of conception.

This ovulation calculator allows you to find out when you'll be most fertile, and what your due date would be if you got pregnant on these dates.

Ovulation calculator

What was the first day of your last period?

What is your average cycle length?

Are you ready to conceive? Take our quick quiz to find out.

For the best chance of getting pregnant, you need to maximise the chance of your fertile egg and your partner's sperm getting together. You can only get pregnant on the few days each cycle around ovulation, when an egg is released.

When is the best time to conceive?

To increase your chances of getting pregnant, you need to get your fertile eggs and your partner's sperm together as often as possible. You can only get pregnant on the few days each cycle around ovulation, when an egg is released.

How does the menstrual cycle work?

  • Your cycle starts on the first day of your period and continues up to the first day of your next period.
  • At the same time, eggs begin to mature in the ovary.
  • The lining of the womb thickens ready for fertilisation.
  • During ovulation your cervical mucus becomes thinner and clearer to help the sperm reach the released egg.
  • About 10 to 16 days before the start of your next period, an egg is released from one of the ovaries (ovulation).
  • If sperm is present at the moment of ovulation, or some time during the next 24 hours, the egg may be fertilised.
  • If the egg has not been fertilised, the egg is re-absorbed by the body, the hormone levels drop, and the womb lining is shed. This is the beginning of your next period.

Read more here about how pregnancy works

Conception and sex

To boost your chances of conceiving, aim to have regular sex throughout your cycle so you know that there should hopefully be good-quality sperm waiting for the time that the egg is released. An active sex life is all most people need to conceive.

If you are quite sure when you ovulate each month you can give yourself the best chance of getting pregnant by having sex in the days leading up to ovulation. Continue having sex during ovulation. After this your fertile time will be over for that cycle.

Taking a pregnancy test? Read about how pregnancy tests work.

How to spot the signs of ovulation

Ovulation usually happens about 10 to 16 days before the start of your next period, so  it helps to know your cycle length before you start trying to conceive.

You may never have considered when you might ovulate within your cycle, and if you have been using a hormone contraceptive such as the Pill, you won’t have had a natural menstrual cycle for a while.

As a first step, mark on your ovulation calendar the dates that you bleed during a period. You can then count how many days from the first day of your period to your next period to work out the length of your cycle.

Cervical mucus changes

The cervix secretes mucus throughout the menstrual cycle, starting off sticky white and gradually becoming thinner and clearer.

Before and during ovulation the mucus increases and becomes much thinner, slippery and stretchy. Women often compare it to raw egg white.

This thinner mucus is designed to help the sperm swim easily through it. It indicates that you are in your fertile phase, so this is the time to have sex if you want to get pregnant, but use contraception if you do not!

The last day you notice the wetter secretions is sometimes known as ‘peak day’ and for most women this occurs very close to the time of ovulation.

Temperature

You can also find out about your menstrual cycle by keeping a note of your temperature each morning when you wake up. Your temperature rises by about 0.2°C when ovulation has taken place.

As it is only an indicator that you have ovulated, and doesn’t tell you when your fertile time starts, this is not very useful for most women.

Using ovulation test kits (also known as ovulation predictor kits)

Ovulation predictor kits are available from chemists and are fairly simple to use. They work by detecting a hormone in your urine that increases when ovulation is about to take place.

The simplest ovulation test kits check for luteinising hormone (LH), which surges 24-36 hours before ovulation. This will help to identify the best two days for conception, although a woman can be fertile for a day or so before and after this time.

It is best to become familiar with your usual menstrual cycle to help figure out when you should start testing. If you have an irregular cycle then an ovulation predictor kit can help you identify the time of ovulation, but expect to use more of the test strips.

Sources

  1. Macdonald S, Macgill-Cuerden J (2012) Mayes’ midwifery: a textbook for midwives, 14th edition, London Balliere Tindall

 

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Last reviewed on June 13th, 2017. Next review date June 13th, 2020.

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Comments

  • By Gladys (not verified) on 18 Oct 2018 - 11:45

    Hi am Gladys , I received my period on 3rd -8th October, I had unprotected sex on 14th ,15th,16th $ 17th ,I am married and I want a baby... Could I be pregnant, then after 17th I experienced tender and breast ache which I usually have during my cycle ..kindly help

  • By Midwife @Tommys on 18 Oct 2018 - 11:56

    Hi Gladys, Thank you for your comment.

    As you have had unprotected sex during your cycle then there is every chance that you may be pregnancy. Wait and see if you miss a period and then do a pregnancy test to check for pregnancy. Take Care, Tommy's Midwives x

  • By ELAINE SALAZAR (not verified) on 9 Oct 2018 - 18:36

    I WAS OFF THE DEPO SHOT ABOUT MAYBE. 6 MONTHS MORE OR LESS. I HAD RELATIONSHIP WITH A FRIEND ON AUGUST 12. HAD MY PERIOD. ON AUGUST 18. AND HAD ANOTHER RELATIONSHIP WITH A REALLY CLOSE FRIEND. ON AUGUST 20TH. MY PERIODS ARE IRREGULAR SINCE I HAD BEEN USING THE DEPO I JUST WANT TO KNOW IF I GOT PREG WITH THE FIRST RELATIONSHIP,, OR THE SECOND????

  • By Midwife @Tommys on 11 Oct 2018 - 11:39

    Hi Elaine, Thank you for your comment.
    As your periods are irregular it is difficult to say when you ovulated and who would be the potential father to your baby. If you are unsure of how many weeks you are then we would suggest that you see your GP who can refer you for a dating scan to see how far you are in your pregnancy. Take Care, Tommy's Midwives x

  • By Juliet (not verified) on 6 Oct 2018 - 10:52

    My last menstrual date was 23th to 25th september and I had unprotected sex all through my period. Then after my period ended I had sex on the 26th, 27th and 29th is it possible for me to get pregnant

  • By Midwife @Tommys on 9 Oct 2018 - 12:10

    Yes, It is theoretically possible to get pregnant at any time during your cycle if you don't take precautions.

  • By Crystal (not verified) on 2 Oct 2018 - 20:04

    I started my period Sept 27 after not having one for over a year. Oct 2 I had unprotected sex and he ejaculated in me. I literally stopped bleeding in the middle of intercourse (not before or after). Is it possible to get pregnant as a result?

  • By Midwife @Tommys on 4 Oct 2018 - 16:22

    Hi Crystal, Thank you for your comment.

    If you have had unprotected sex then there is every chance that you could fall pregnant. Wait for your next period and if it is late then do a pregnancy test to see if you are pregnant. Take Care, Tommy's Midwives x

  • By Isabel (not verified) on 27 Sep 2018 - 15:20

    I had my period on the 9th for 5 days I had unprotected sex on the 13th the 17th and 18th could I be pregnant ?

  • By Midwife @Tommys on 27 Sep 2018 - 15:44

    Hi Isabel, Thank you for your comment.

    It is still very early to tell if you are pregnant if you only had your period on the 9th September but if you have been having unprotected sex with no other form of contraception then there is every chance that you may fall pregnant. We would advice that you should wait to see if you miss your period and then do a pregnancy test. Hope this helps, take care, Tommy's Midwives x

  • By Hellena (not verified) on 24 Sep 2018 - 08:54

    I got my periods 19 to 22 of September and i need pregnant..so which is the best date to have unprotected sex??

  • By Midwife @Tommys on 25 Sep 2018 - 15:02

    Thank you for your comment.
    You should try to have sex every 2-3 days throughout your cycle as this can maximise your chances of conception. Your most fertile time is around ovulation which occurs 10-16 days before the start of your next period. If you know when you ovulate each month you can give yourself the best chance of getting pregnant by having sex in the days leading up to ovulation. Continue having sex during ovulation. After this your fertile time will be over for that cycle.
    The following link has more information that you may find helpful-

    https://www.tommys.org/pregnancy-information/planning-pregnancy/how-get-pregnant

    Take care
    Tommy's Midwife

  • By Laeticia (not verified) on 23 Sep 2018 - 15:40

    I had my period on the 11-14 September and from that 14th I have been having unprotected sex till today the 23 September can I be pregnant?

  • By Midwife @Tommys on 25 Sep 2018 - 15:10

    You may be pregnant-you are your most fertile around ovulation which usually occurs 10-16 days before the start of your next period
    If you know when you ovulate each month you can give yourself the best chance of getting pregnant by having sex in the days leading up to ovulation. Continue having sex during ovulation. After this your fertile time will be over for that cycle.
    The best way to find out is to take a pregnancy test-some of these tests are very sensitive to hormone levels which change once you are pregnant and can be used even before you have missed a period

    Take care
    Tommy's Midwife

  • By Debby (not verified) on 16 Sep 2018 - 13:26

    Am having irregular menstruation ,what is the assurance that I can get pregnant, am about getting married and am sacred

  • By Midwife @Tommys on 17 Sep 2018 - 10:08

    Hi, It isn't possible to guarantee that you will have no problems conceiving. The best thing you can do is to lead a healthy lifestyle with good nutrition and exercise. Our new web tool #areyouready gives good advice about how to increase your chances of a healthy and happy pregnancy.

  • By Anonymous (not verified) on 14 Sep 2018 - 21:11

    I got my period on 27 may and have sex on the 3 June since June I didn't nt got my period

  • By Midwife @Tommys on 17 Sep 2018 - 10:12

    It would be sensible with these dates to do a pregnancy test or arrange to see your doctor. Best wishes

  • By Jasmine (not verified) on 7 Sep 2018 - 22:09

    Hi my last period was August 18-23 I have unprotected sex September 1-5 can I be pregnant?

  • By Midwife @Tommys on 12 Sep 2018 - 09:38

    Assuming that you have a 28 day cycle then you would be most likely to be fertile around those dates so conception is possible. I would suggest you do a pregnancy test to confirm whether you are pregnant or not.

  • By Ashley (not verified) on 7 Sep 2018 - 19:04

    Hi, so I recently just had unprotected sex on September 7th (today) I checked my period tracker and it let me know that today was my last day of being fertile. Is there a possibility to get pregnant on the last day of ovulation? So far I’ve read that it’s more likely to get pregnant within the first 24 hours of ovulation so I’m a bit confused on whether or not the last day of ovulation matters as well.

  • By Midwife @Tommys on 12 Sep 2018 - 09:31

    Your period tracker would only tell you when you are likely to ovulate, not the exact day of ovulation. Ovulation generally occurs 10-16 days before your next period-this is considered to be when you are most fertile-you can only get pregnant on the few days each cycle around ovulation, when an egg is released.The following link has more information for you-
    https://www.tommys.org/pregnancy-information/planning-pregnancy/ovulation-calculator

    Tommy's Midwife

  • By Danait aron (not verified) on 4 Sep 2018 - 18:37

    My period come on aug 3 and lasts on 5 aug and i made unprotected sex on aug 17 actually my period must come on 2 or 3 sep but this 3 days when i smell something or eat something i feel nauseous and in morming two days i vomit and i cramp on my stomatch wt can it be

  • By Midwife @Tommys on 7 Sep 2018 - 13:34

    Hi,
    I would suggest for you to take a pregnancy test to see if you are pregnant. Also I would advise for you to be taking folic acid if there is a chance that you may be pregnant. If the pregnancy test is negatively and you continue to have symptoms and feel unwell and then I would suggest to see your GP.
    Best wishes
    Tommy's midwife

  • By Kelly (not verified) on 3 Sep 2018 - 21:43

    I had unprotected sex on the 1st of July and the 7th and then after aswell in July. Then got my period on the 11th of July which lasted until the 16th of July. I then had sex so many times after did I conceive before or after my period? I'm almost 8 weeks pregnant

  • By Midwife @Tommys on 7 Sep 2018 - 13:20

    Hi Kelly,
    You will have conceived after your period, at about the end of July.
    Best wishes
    Tommy's midwife

  • By Vydehi (not verified) on 2 Sep 2018 - 11:03

    My periods was started ....yesterday when it is better sex to get pergant

  • By Midwife @Tommys on 7 Sep 2018 - 14:49

    Hi Vydehi,
    We would advised regular sex throughout your cycle however for most women, ovulation usually occurs mid cycle, about 10-14 days before your next period is due and this is the most likely time to get pregnant. I would advise for you to be taking a folic acid supplement now if you are not already.
    Best wishes
    Tommy's midwife

  • By Koko (not verified) on 31 Aug 2018 - 22:42

    I had my last period on the 31 of july 2018 which lasted for 5 days, i had sex on the 18 of August ... Today is 31 and am yet to see my period.

  • By KoKo (not verified) on 31 Aug 2018 - 10:24

    I got my period on 9 aug 2018 to 11 aug 2018. I had unprotected sex from 14 aug to 26 aug.Am I pregnant?

  • By Midwife @Tommys on 31 Aug 2018 - 15:42

    Hi KoKo,
    The only way to know if you are pregnant is to take a pregnancy test, if your period is delayed then I suggest this is what to do.
    Best wishes
    Tommy's midwife

  • By Victorine Samuel (not verified) on 31 Aug 2018 - 07:07

    My last menstrual date was 28th to 30th July and I had unprotected sex on 31st July and August 1st is it possible for me to be pregnant

  • By Midwife @Tommys on 31 Aug 2018 - 15:27

    Hi Victorine,
    There is always a possibility of becoming pregnant when you have unprotected sex, if you period is delayed then i would suggest to take a pregnancy test to see if you are pregnant. If you are having unprotected sex then it is important you are taking a folic acid supplement in case you do become pregnant.
    Best wishes
    Tommy's midwife

  • By teddy (not verified) on 29 Aug 2018 - 16:19

    my menstral cycle was on 27-29/8/2018 when exactly should i have sex to conceive?Plz help!

  • By Midwife @Tommys on 30 Aug 2018 - 13:50

    Hi Teddy, Thank you for your comment.

    If you have a regular cycle then ovulation tends to happen around day 14 of your cycle. If the first day of your last period was the 27th August then you should ovulate around the 10th September so having unprotected sex around you most fertile time can increase your chances of conception. But having regular unprotected sex throughout your cycle can also help with conception as well. Hope this helps, Take Care, Tommy's Midwives x

  • By Chelsayxoxo (not verified) on 21 Aug 2018 - 11:19

    Hello I got my period on the 4th August 2018 lasted about 5 days. Had unprotected sex on the 18th August and the 20th. We are tring to concive and my periods are usually very irregular when is the best time to take a test and how can I tell when I'm ovulating

  • By Midwife @Tommys on 22 Aug 2018 - 11:15

    Hi Chelsayxoxo
    Have a read of the article above for how to work out your ovulation window (and try using our ovulation calculator give give yourself the best chance of conceiving.) https://www.tommys.org/tags/ovulation

    Waiting at least a week after a missed period may give you the most accurate result. Results may also be more accurate if you do the test first thing in the morning, when your urine is more concentrated. Urine home pregnancy tests are about 99% accurate.

    Good luck!
    Tommy's Midwife

  • By kelly (not verified) on 13 Aug 2018 - 08:46

    I had my period on August 2nd to 4th 2018. I have unprotected sex with my partner from 6th to 12, can I be pregnant. and I don't know when is my Ovulation days that's why I want to have sex till 19th of August. Can someone calculate it for me and tell me my Ovulation days and am 28 days cycle

  • By Midwife @Tommys on 15 Aug 2018 - 12:43

    Hi Kelly
    Any unprotected intercourse can result in pregnancy.
    If you are not trying to conceive, then i suggest that you use contraception.
    You will need to wait until your next period is due before doing a pregnancy test as you only had intercourse last week so it is too early to tell. You can use the ovulation tool -see below- to work out roughly when you may ovulate.
    https://www.tommys.org/pregnancy-information/planning-pregnancy/ovulation-calculator
    All the best
    Tommy's Midwife

  • By Sirri (not verified) on 17 Aug 2018 - 23:25

    Pls help me calculate my ovulation it start on the 8/16/2018 / pls help me calculate my ovulation period

  • By Midwife @Tommys on 20 Aug 2018 - 14:57

    Ovulation is usually about two weeks after the start of your period. If your last period started on 16th August, Ovulation would be approximately 1st September if you have regular periods every 28 days.

  • By Jaykey (not verified) on 7 Aug 2018 - 20:04

    Hi I am Jaykey... i had a baby on July 25, 2018 by operation. Yesterday I had an unprotected sex with my husband. Will it lead to pregnancy?
    Plz plz plz... rply

  • By Midwife @Tommys on 9 Aug 2018 - 15:55

    Hi Jaykey, thank you for your comment.
    If you are not using any form of contraception and having unprotected sex then there is every chance that you may become pregnant. We would suggest that if you don't want to become pregnant then you need to use a form of contraception in the future. Take Care Tommy's Midwives x

  • By Kara (not verified) on 9 Jul 2018 - 05:02

    I had my period last May 7 and then I had unprotected sex last May 30 and 31. I did have some sort of mens last June 9. Can I be pregnant?

  • By Midwife @Tommys on 9 Jul 2018 - 11:26

    Hi Kara, It is only possible to confirm a pregnancy at this stage by dong a pregnancy test. If you think that your last period was unusual and that you have had unprotected intercourse, it would be sensible to do a test.

  • By dinah (not verified) on 8 Jul 2018 - 08:56

    My period started on the 7th June and I had unprotected sex on the 2nd july n i haven't seen my period as at today, 8th July meanwhile my predicted date of my next period was suppose to be 5th july

  • By Midwife @Tommys on 9 Jul 2018 - 11:21

    In order to confirm a pregnancy at this stage, you would have to do a pregnancy test. The test will confirm or deny that the pregnancy hormone is present which is needed to sustain a pregnancy.

  • By mere (not verified) on 30 Aug 2018 - 02:00

    Hy...i had my period from 7th to 10th August,2018 and than i had unprotected sex 12th...and now am starting to get some symptoms of pregnancy like breast aches and fatigue....is there a possibility that i can be pregnant

  • By Midwife @Tommys on 30 Aug 2018 - 12:47

    Dear Mere, Thank you for your comment.
    If you have had unprotected sex then there may be a chance that you are pregnant. See if you miss your next period and then do a pregnancy test. If you have unprotected sex without using any form of contraception then there is every chance of getting pregnant. Take Care, Tommy's Midwives x

  • By Gift (not verified) on 26 Jun 2018 - 08:09

    Hi I'm gift, I had my period on 7 to 10 of June, n I had sex on the 17 , can I be pregnant.

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