You want to know the dates of your next period, ovulation or due date? You came to the right place. If you’re in a hurry you can go straight to our menstrual cycle calculator (click here) or Infographic with key information about calculating your period (click here).
Check the full table of content below.
Table of Contents
- Introduction
- Period & Ovulation Calculator
- How Do Menstrual Cycle Calculators Work?
- Using a Period Calculator
- How To Calculate Your Next Period & Ovulation Infographic
- Understanding the Menstrual Cycle Properly
- Understanding Your Next Menstrual Cycle and Fertilization.
- Some Important Information Regarding the Calculator
- Learn more
- Frequently Asked Questions
Introduction
If you want to stand the best chance of getting pregnant, then you need to know when you are ovulating. This is the time of the month when women are in their most fertile period. Ovulation usually happens around day 14 of the cycle [1]), while there is a greater chance of a sperm reaching the egg and fertilizing it.
However, one of the biggest problems and question that people have is knowing how to calculate their next ovulation date and when is the best time to aim for intercourse. This is where technology can come in handy. You can use an ovulation calculator, like the one below, to get a rough estimate of when you are going to ovulate next.
Ovulation & Period Calculator
Use this period calculator to calculate your next period (menstruation), fertile period, ovulation, and due date. To give you an estimate as to when those time frames are, please provide the requested information and press the Calculate button (results will be shown below, together with a fertility calendar):
When did your last period start?
How many days did it last?
How long is your cycle?
Below are the results based on the information you provided:
Your next menstrual period is expected to start on
Your next most fertile period is from to
If you conceive within this timeframe, your estimated due date will be
- Pre-Period
- Period Days
- Post-Period
- Peak Ovulation
Please note that this is only an estimation of your menstrual cycle
A period calculator is not the same as talking to a healthcare professional, so this is just to aid you in coming up with the most accurate calculation possible, on your own.
Also, keep in mind that these calculators will be useful to women with a fairly regular menstrual cycle. For women with irregular menstrual cycle tracking other ovulation symptoms or using an ovulation predictor kit might give more accurate results, all of which we’ll cover later one.
How Do Menstrual Cycle Calculators Work?
Menstrual Cycle Calculators vary in complexity. Some will ask you for information such as your average body temperature, as well as various other bits and pieces about what your body is currently going through.
While there are women who measure their basal body temperature, it’s not something that the everyday woman uses.
However, it is a rather accurate way (when done 100% correctly) to determine when a woman is ovulating.
Some feel that these types of cycle calculators are “overkill”, but for those who are using the basal body temperature to prevent and plan a pregnancy, they have this information handy.
If you aren’t into this type of strict monitoring, a simple calculator like the one provided here can give you really good results and help you plan.
Using a Period Calculator
The first thing that the period calculator will ask you is the date of your last period. With so many apps available now, this should be information that is readily available.
And just remember, when calculating your period, you use the first day of your last period. This was the beginning of your cycle.
If you don’t know the exact first day, calculate back from the last day however long it lasted, and start tracking now. Especially if you are trying to get pregnant.
Some will use a menstruation calculator to figure out when to expect their periods and when to expect PMS. PMS is due to the change in hormones that cause periods and pregnancy.
When you are pregnant or during your period, these emotional and physical symptoms subside [2]. Some women can then plan to change their diet a few days before they expect PMS and help to alleviate some of the symptoms.
The next piece of information that you will be asked for is the average length of time between your periods. This is the length of the menstrual cycle. Of course, the human body does vary wildly here, and whilst some months there could be 30 days between your period, others it could be as low as 25.
However, you are only after an average here. Being as accurate as possible is important as this will affect the results that you are given which can have a profound effect on when the calculator tells you is the ideal time to try for a child.
Finally, you will be given your results. Based on the information you provided, it will calculate when your next period is anticipated and also your fertile period which is when you stand the best chance to get pregnant.
How To Calculate Your Next Period & Ovulation Infographic
Understanding the Menstrual Cycle Properly
While you may already have a fair understanding of your own menstrual cycle, there are women who have cycle lengths that vary. Sometimes, your own cycle can be as short as 23 days on cycle and 28 or 30 days the next.
When a variation in menstrual cycle length occurs, it usually happens before you ovulate. This is referred to as the follicular phase which encompasses menstruation as well and ends when you ovulate [3]. A woman generally ovulates between days 12-16 of their cycle which is the start of the luteal phase [4].
There is a multitude of reasons as to why your period could be altered, be it stress or medications, even weight gain/loss or travel. Unless you think you are pregnant, it could be a myriad of reasons that have your period coming irregularly.
Understanding Your Next Menstrual Cycle and Fertilization
If you are trying to get pregnant you need to understand how the menstrual cycle works. The process starts when the thick lining of your womb starts to break up due to the decrease in estrogen and progesterone levels.
Without a sufficient amount of these hormones, your body will shed the lining and it will start to prepare for your next menstrual cycle.
However, if a sperm does make contact with and fertilizes the egg, it will close all pores to prevent more sperms from getting in there. The fertilized egg will stay in the fallopian tube for 3-4 days and then move to the uterus and attach to its wall, staying there for the long haul of pregnancy.
Your body will produce human Chorionic Gonadotrophin (hCG) or pregnancy hormone right away (which can be seen within 6-8 days by a blood test and can take about 2 weeks if not longer to be seen in urine tests) [5].
The body will continue to produce the required estrogen and progesterone hormones so that the womb lining will not be shed and the placenta can grow mature enough that it can support the pregnancy.
Some Important Information Regarding the Calculator
The period calculator above also comes with a fertility calendar. You can navigate through different months by clicking on the NEXT 2 MONTHS and PREVIOUS 2 MONTHS links. This allows you to plan and prepare for your fertile and menstrual periods in the upcoming months.
What you do need to remember though is that the information isn’t 100% accurate as it is impossible to predict the human body.
Your fertile period gives you a good range in when to have intercourse to potentially get pregnant. You can learn more about the likelihood of conception in this article.
That being said, the menstrual calculator is still an extremely useful tool. It provides a simple way of knowing when to anticipate your next period and when is the best time to try for getting pregnant.
This could be a huge help for those with busy schedules to plan their days to start their family.
Learn more
Want to learn more about your menstrual cycle? Find out how does the Fertility Calculator work or how to to calculate your period manually.
Want to know if you’re pregnant? Take this online pregnancy test, read more about the most common reasons why your period might be late or find out when it’s the best time to take a home pregnancy test.
FAQs
How do I calculate the length of my cycle?
Can I have sex during my period?
What is the average length for periods?
My period is really heavy; what can I do to change that?
Can I get pregnant if my periods are irregular?
How do I know if I need to see a doctor because my heavy periods?
Can I prevent PMS?
Do you have any other question about your period, ovulation, pregnancy or other related topics? Check out our Frequently Asked Questions page.
References
- Your Fertility. Women’s Guide to Getting the Timing Right [link]
- Mayo Clinic. Premenstrual Syndrome (PMS). [link]
- Better Health Channel. Menstrual Cycle. [link]
- see above #3
- WebMD. Pregnancy and Conception. [link]
- Eleanor Jones via Cosmopolitan. 10 Questions Period All Guys Want Answered [link]
- Playtex. Period 101. [link]
- The University of Iowa. Birth Control Pill Fact Sheet. [link]
- WebMD. Slideshow: Answers to Your Top period Questions. [link]
- see above #9
good afternoon! I got the depo shot feb 2015 then was supposed to get another shot on april 23rd 2015 but missed it started my period on the 24th and it literally didn’t stop (spotting, heavy flow, light flow all together throughout) until june 16th. I had unprotected sex the 3rd of july, 5th and 8th. No period yet….should I keep waiting ?
Hi there, the first day of my last period was the 17th of June, my period was due on the July 15th but still nothing has happened. I keep thinking I’m getting it because I have had PMS for about a week now, but it’s still not here! I had unprotected sex from the 23rd June to the 27th of June. I took a pregnancy test 3 days ago and it was negative. What’s happening!?
I saw my period May 21-27, and I had unprotected sex on the 14 of June…then saw my period on the 20th of June. Do you think I might be pregnant?
It seems you may not be pregnant. It is possible, however, to have a period and still be pregnant so it’s best to take a pregnancy test.
I had my period from 12 June to the 17th, I know I am a few days late now and was wondering if it is worth doing a test as me and my boyfriend have struggled to conceive this past year.
If you had a 28 days cycle your period was due on July 10. You can take a pregnancy test now to confirm if you conceived during your last fertile window.
I had my period 3 days before due time last month and it’s reoccurring again this month, I always have a 28 days cycle, but I always have pregnancy symptoms because I have always had unprotected sex, I took home test twice but its negative, what could be the problem. thanks very much.
Hi Steffy, my period started on July 10 up to July 15. My boyfriend and I had unprotected sex on July 15, 17 & 20. May I know what my ovulation date is? Or what dates should we have sex in order to become pregnant. Thanks in advance.
It is important to know the length of your cycle in order to know when you are ovulating. I need that information before I can advise you of your fertile days. If you have a 28 days cycle, then you would ovulate from July 22 to 26.
I had sex wid my boyfriend on June 8 and my period started on June 18. My period date is July 16 but I’m not having my period what’s wrong? Please help me. Should I worry that I’m pregnant?
If you did not have unprotected sex from June 30 to July 04, then you would not be at risk of getting pregnant. If you had sex during that time then you can take a pregnancy test now to confirm. If not, then your period may just be late because of any physical or psychological changes in your body.
Hi Steffy! Based on this calculating app, my fertile days started on the 18th of July and long before then I have been having sex. Hubby wants to travel tomorrow; I want to know the risk of me being pregnant presently since I won’t be able to have sex till next week.
The possibility of getting pregnant is always very high when you have sex just before and during your fertile days. Good luck!
I just had my period on the 4th of July and I got off my period 6 or 7th of July but my period are suppose to come on the 27 of the month but I also had had sex on the 4th of July and didn’t know I was on my period and he didn’t pull out I don’t know what to do
Ok I had my period on June 14 -throw June 17,2015. & I started my period on July 19,2015. & I’m 2 weeks late on my period what does that mean
My period came early…Is there any problem? Please respond.
It is normal for your period to be early. This may be due to any change that is happening in your body. Stress, anxiety or hormonal changes may be contributing factors.
I had my period from 19th of June to the 23rd..then I had sex on 25th, 26th and 30th of June – now I’m 4 days late. Could I be pregnant?
The length of and regularity of your cycle are necessary to answer your question. Taking a pregnancy test by July 22 should give you accurate results.
Can I get pregnant a few days before ovulation period?
Technically, yes. Because sperm can live for up to 72 hours, some doctors encourage their patients to start having sex at least three days before ovulation to increase their chances of conception. The sperm will be ready and waiting for the egg to be released.
Ok, so my last period started on June 22 and ended on June 26 I had unprotected sex all of the rest of that week starting the 26th when my period ended. I have been feeling weird and the entire week after having unprotected sex I was feeling sick and craving things. Could I be pregnant?
If you have regular 28 days cycles, you were fertile on July 04 to July 08. Unless you had sex on those days as well, your chances of being pregnant were very low.
Steffy. I had sex from June 26 to the 29 a few times a day I also had sex on July 3, 4 and 5. So could there be a possibility that I’m pregnant?
You need to confirm the length of your cycle and when were you most fertile. This information is needed to provide a response.
I’m 21 and im trying to get pregnant by my fiance. Last month I had unprotected sex on the 24, and 27 this month I had sex on 1, 4 and 9 my period came on July 12-15 I had sex on the 15, 16, 17, 18, 20 and will continue throughout this month what are my chances of getting pregnant? I feel like I can’t have babies, but really want one, any help?
To increase your chances of getting pregnant, you need to keep track of the number of days in your menstrual cycle. This will help you to chart your fertile days or when you are ovulating. It is best to have sex just before and during your fertile days each month to give you a better chance of becoming pregnant.
Steff my menstrual started jun 22nd and the calculator says my most fertal days were july 4,th to the 8th. So what do you think
Hi me and my partner are trying to conceive.. My period was the 28th June and I have 28 day cycle which would make fertile around the 14th July we had sex around 2 days before ovulation and on the day of ovulation.. My next period is due around 26th July. When’s the best time to do a pregnancy test? Can I do one before my period? Thanks
Hi I had sex March 11 but I had sex on the first day of my period; I was spotting and it was unprotected. It was a 1-time thing with the dude. As my period continued I had cramps and I had my normal period. I’m not sure if you can get pregnant if you have sex on your period. But I’m concerned because I got back with an old boyfriend March 24 and I didn’t get my period as I was suppose to… So I’m not sure whose baby it is the first one or the second one. Yes this sounds pretty bad. But I’m 19 weeks preg now. I’m hoping it’s my boyfriend’s and not the dude I slept with for one night. When I went to the doctor April 13 the doctor told me I was 5-6 weeks along. Who’s could it be ?!!!
The best way to determine who fathered the child you’re carrying is to do a DNA test. However, whether or not you can get pregnant on your period depends on the length of your cycle. If you have a cycle that is 28 to 30 days or longer, it is unlikely that you would get pregnant while you’re having a period. If you have a shorter cycle, it is likely that you could get pregnant from having sex during your period.