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





I have been trying to conceive for the last six years. During that time I became pregnant a couple of times, but they resulted in a miscarriage. This was three miscarriage. The doctors said that they saw an empty amniotic sac, but no baby I could not understand what was going on. Last year I had a surgery done to remove a fibroid that was growing on my left ovary, the fibroid damaged my left ovary that the doctor had to remove my left ovary leaving me with a right ovary. I am now 33 years old and I worried if I’ll ever have any children, I thought I need to hurry and try to have one fast. I went on-line in search of a product that would help me conceive fast until i met Dr. Miracle on the internet who help to cast a spell that make me conceive a baby contact him on -removed- or call him on +2347060552255
I had a test strip 2days ago it was negative andam supose to see me period yesterday I did not see my period Å̶̷̩̥͡•̸Ϟ I pregnant
This is a great question. Most pregnancy tests are only highly reliable four days after your missed period. Also, not every woman has a regular cycle of the same number of days each month. It is best to wait a week and test again.
The first day of my last period was February 15, 2014. I had sex on the 21, which was two days before my cycle ended. I have not started yet. Could I be pregnant?
It is unlikely that you would get pregnant that close to the end of your cycle, but not impossible. Cycles can be late or missed for several factors, some physical and some environmental. Take a pregnancy test or check with your doctor for a more concrete answer.
I saw my period last February 18th , it’s 19th today and have not come did a pregnancy test which was negative on the 17th and I have milk discharge each time I squeeze my breast….do you think am pregnant?
While a milky discharge can be a symptom of pregnancy, it is usually not the first symptom you experience. A milky discharge resulting from squeezing the breast can have several other causes including, but not limited to: clogging of the breast ducts, inflammation, breast injury, non-cancerous brain tumors, certain medications, certain herbs, widening of the milk ducts and hypothyroidism.
If it is a concern, it is best to address it with your doctor. Not every woman’s cycle is 28 days, and most pregnancy tests don’t work until at least four days after you expect your period. It is best to wait seven to ten days before expecting a reliable test.
Pls i having hot body most especially in the midnite. Pls, some one help me.
Hot flashes can be due to hormonal changes in your body. Hormone fluctuations occur naturally during the course of any menstrual cycle, but can also be a symptom of menopause or pre-menopause or other physical conditions. If you are very concerned about this, please check with your physician.
Hey guys my last period started on the 10th of feb 2014,but there was only 28days in that month still no sign of my periods this month n its now the 14th march.we have been trying for a baby for 1 year n half n have been disappointed up to now.do u have any answers on this??
It is possible that you are pregnant. However, it is also possible that your period is simply late. Try taking a pregnancy test. If it is negative, try taking one again. If you think you may be pregnant for some reason, and the test doesn’t show it, it is best to see your gynecologist. Just keep in mind that a missed or late period that isn’t a pregnancy, isn’t in itself a cause for alarm. Periods can be late or missed due to stress, changes in sleep or diet, or various other factors.
I got them on the 18th
Hi my last menstrual cycle was on feb.18th and it lasts usually 5 days it only lasted for 4 and yesterday march 11th evening I started bleeding again what could this mean? Any suggestions? Answers?
Melissa, I am curious about your definition of bleeding. Was it a constant flow? Was it intermittent spotting? Spotting can happen for various reasons throughout your cycle. It could also just be that you had a slightly shorter cycle this month due to changes in diet, sleep, exercise or stress.
I had my period on 21/2/2014 …and according to my P.Calculator my next period should be on 26/3/14 ….
but Im getting these breast sores this time a li’l earlier(my signs for period)today is only 12th ….is this normal?
Sore breasts can be due to hormonal changes, occurring any time in your cycle, whether you are pregnant or not. However, don’t rule pregnancy out until you take a test, about a week after your projected period date.
today been 8 0f march 2014 is my most fertile day, when is the best time to make love and get pregnant.
now! 🙂 best time is few days before and on the day of ovulation
Hi, I had my period on the 19th of Dec 2013, from there I missed my period in January, I thought I was pregnant I took a home pregnant test but was negative. on 20 of February 2014 my period stated. I have been trying to conceive since 2012 but no luck. my cycle is irregular sometime it takes up to 43, sometime more than 60. is this normal/ can somebody help me, I want a baby.
Hello I I stopped taking the microgyn 30pill last month had my period five days later on 30th I ovalted on the 22nd of February wen will my next period be due as worrying about becoming pregnant
I had my period the 28 th of Jan. When should I have it by?
For my fiance and I have been trying to conceive, therefore I’ve been keeping track. I’m unsure of my exact cycle time but it is around 28.
Hi, according to your period calculator and my period tracker app I should have my period on Jan 27, 2014 and my lmp was on dec 22, 2013. Today is Feb 22 and I still haven’t got my period yet. I already tried 3 home pregnancy tests and it all came out negative. What’s happening? am I pregnant? Please help
It is possible that you are pregnant, but we sometimes miss or skip periods because of hormone imbalances, excess stress, or many other reasons. If you don’t have your period before your next period date, it is best to consult with your gynecologist.
I am girl of 22,did my last period on 21/1/2014,and according to your period calculator, said I should be due for another 18/2 of this month,today is 21,and am yet to see it,Tho I had sex on 1st of this month and my boyfriend ejaculate….please is it that am pregnant??
In this case, you would have had sex on day 11 of your cycle. It is possible that you are pregnant. However, periods are commonly late. Wait a few more days and test again. If you don’t get your period in the next 7-10 days test again. If you receive your period in the next 14 days, try consulting a doctor for a blood test.
I did the previous period on the 15/12/2014 and the last period on the 22/01/2014. When is my ovulation period
Hi, It’s not possible to tell the exact date of ovulation by the length of your menstrual cycle. Some women ovulate around the 14th day of their cycle. However, not all women do. You can try to pinpoint your ovulation by tracking your cycles or using ovulation testing strips. You can buy those online. You can more accurately find when you are ovulating by tracking your cycles, cervical fluid consistency and base body temperature. You can find more information about this in Taking Charge of Your Fertility by Toni Weschler. You can read these posts for more info.
One more option is to get an ovulation kit
Hi. I just came upon this page and I did the menstrual cycle calculator and according to this I should have gotten my period on jan22 2014. My last period was on dec 25. It’s 7 days long and 28 a days in between. Now today is jan 28 and I still haven’t gotten my period. I’m a little freak out but trying not too. When should have gotten my period? I thought I would have gotten it on jan 28 but didn’t. I’m a little confused with these dates. Need help please. Thanks
Hi Jen. These little delays are not uncommon. this article discusses some reasons why this may happen and what to do about it