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 had sex with my boyfriend on the first or second day in my period unprotected. Although we have been accepting a baby, but I saw my period on 31 to 3 of February and it was smelling bad. Is it a bad sign of infection or anything, can i till be pregnant? when are am I suppose to be ovulating and are am i suppose to get pregnant
The smell is not related to pregnancy, but could be related for an infection. I would seek over the counter help for that. For the other questions, please visit our FAQ page. Your questions can be answered here 🙂
I started my period on the 15th to 17th of January and i had sex on the 29th, I want to know if I am save
My last period was on Dec 5, 2015. I missed my period for january 2nd and the 30th. I took a urine test at the hospital, but it was negative. What should I do?
There are numerous reasons why someone would miss a period. If you missed a period and you are not pregnant, you might want to know why this happened. Some of the causes of a missed menstrual cycle include: stress, change in regular schedule, travel, illness and use of certain medications. It would be best to consult your doctor for help in identifying which factor is causing the delay. For more information please visit our FAQ page.
My last period was on December 30th 2015 and it lasted until January 2nd 2016. It’s now February 4th 2016. In between January 2nd and January 15th I had intercourse with my boyfriend unprotected. Could I be pregnant?
There is a chance you could be pregnant. Depending on when your ovulation window begins, and if you are having any symptoms. You could take your pregnancy test in about 4/5 days, just to see if you are. This chance is not likely, but not impossible.
I have a question, i hope you will help me. my girlfriend last period september 8 to 11 2015.and now shes pregnant and ultrasound says june 28,2016. and her cycle 30 to 32 i guess. what date she got pregnant. I’m confused what date she concieved. thank you so much, hope you will reply
2 weeks from the first day of her last period if she has a 28 day cycle 🙂
My best guess would be between the dates of October 2nd-October 10th by the information you provided 🙂
I really need some answers, i missed my period on January and today is February 3, I went to the nursing stations yesterday I had an negative pregnancy test I was expecting because I been having unprotected sex and this was my first time that I have missed a period and was asked to come back next week and today I helped out my brother in law to carry a dresser and a few minutes later I had a bit cramps like pain and achy legs and I had some bleeding that was light pink and got darker when I used a rest room dark pink and now it’s kind of red, has anyone ever experienced this?
Hi,If you are indeed pregnant the spotting or bleeding you saw could be a threatened miscarriage,i suggest you don’t lift anything heavy until you find out for sure if you are pregnant.
The first day of my last period was on Jan. 2 and had sex on January 9. When is my next period? I’m feeling unusual abdomen cramping.. Could it be possible that I’m pregnant now?
Your next period should have started around February 3rd-February 10th, around then. If you are experience cramping, it could be related to you being due for your period soon, pregnancy, or something else. You can take a pregnancy test as soon as you would like to, and if the cramping consists extreme I would suggest seeking professional help!
I had my period on dec 31,2015, I had sex on january 29, 2016. Its possible that I am pregnant? Thanks
Did you get your period in January? And did you use protection? When you aren’t sure, I always recommend a pregnancy test just in case; they are rather cheap and found easily.
Hello,
I had my period on 4th Jan to 8th Jan when is my next period? Because up-to-date no signs of period. Am 31 and married with three solid years trying to conceive but to no avail what can be this like?
Hey! If you missed a period, or experience a delay, and you are not pregnant, you might want to know why this happened. Some of the causes of a missed menstrual cycle include: stress, change in regular schedule, travel, illness and use of certain medications. It would be best to consult your doctor for help in identifying which factor is causing the delay.
Hi. I started my period in January 27,2016 and it ended January 30,2016. I had unprotected sex on February 3,2016. My fertile window don’t open until February 7,2016. Is there a possibility that I could be pregnant?
There is a possibility, but it is unlikely. Keep in mind that sperm can live inside your body for up to 72 hours. Wait until your scheduled period, and if you miss it then I would recommend taking a pregnancy test just to be certain. Take the test about a week after a missed period should you need to.
I had my period on January 1st to January 4th, I had sex on January 7th, and it’s February 2nd, Could I be pregnant?? I need to know.
there’s a possibility, especially if you have a shorter cycle. read more here
I need an answer, well my last period was December 28 to January 1st, i haven’t had my period since then it’s now February 2, I took a pregnancy test this afternoon it came out negative and I really want a child of my own so I’m asking is it possible that I might be pregnant because I missed a period and try another pregnancy test next week if I still don’t have my period.
I am in your same situation, what ended up happening?
I end up having my period after helping my brother in law lifting up a dresser, I had a pain sore that I couldn’t sleep, I just don’t get it I never missed a period before.
Girl, your next period will be 2 Feb.
Hi! I have a query to ask.
Last Jan.23, 2016 was the day that my girlfriend got her monthly period and it last for about Jan. 27. On the 28th and 29th, she got some spotting, and on the 3oth of this month, we have done the deed.
Since we are aware of what we are doing, I took extra care during our intercourse, even though it is unprotected. After a few strokes, I pull my genitalia to check, and squeezing it, I found a clear fluid on the tip of penis. Because of that, I decide to have a hand-job rather than continuing that scenario to avoid putting my sperm inside her.
Now, my questions are:
1) Is she on the safe zone that time?
2) If she’s in the safe zone that time, is there a possibility that she might get pregnant?
Thanks for your reply! God bless!
Hi, as long as none of that clear fluid (precum) got inside of her then she is save but if some of the precum got inside her there is a chance of pregnancy as women can get pregnant anytime after unprotected sex.
So I spotted January 5,2016 and came on January 6,2016 came off January 8,2016 I had sex January 14,2016 and January 21,2016 I been having pregnant feelings like breast sore, some headache, backache, some pain in my pelvic like a baby is stretching, bloated, hungry all the time also my tubes been tied for 3 years in a half. also when I eat I feel something moving in my belly. But January 30,2016 I had little pinkish discharge I also had sex that day January 31,2016 I was spotting Now February 1,2016. I’m bleeding lite what’s going on. can anybody tell me is this the day I really suppose to come on my period? I thought I suppose to come on February 5
Ok so I had unprotected sex on the 25th of January and on the 30th of January I got my period but I’m feeling unusual cramping in my stomach. Is there a possibility I could be pregnant?
The chances of you being pregnant are low.