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
Hi. i’m pregnant but the 1st day of my last normal period was on the 8th of march 2015. My next period was supposed to come on the 4th of April 2015, but it came late on the 17th and ended on the 23rd of April, this were not normal periods cause they came out with clots and they lasted for seven days. My period cycle is 26days. So to calculate my due date, do i use the normal period date or the date of the period that came late?
Hello. Count it from your normal period date. You should already be having regular visit to your OBGYN clinic to ensure the foetus is developing healthily.
I had my period on October 17 and had sex on November 3. I have gotten what i thought was my period today (November 16), however my period is Brown and i am not sure if it would be implantation bleeding or not. Can you help me??
For you to conceive you would have to be fertile during the time you had sex. The number of days in your cycle is needed to determine this. If you have a 28 days cycle you were fertile from October 29 to November 02, 2015. In this case, your chances of conceiving would be low.
If my last period was October 11-13 when is my next expected period?
Periods are unique and very personal. The date of your next period will depend on your own hormonal levels and the external factors that are affecting your body. You have to wait and see basically when you will have a next period. When it comes you need to count the days from October 11 to the first date for that period. This will help you to confirm the numbers of days in your cycle.
My period came October 24-30 my cycles run 28-40 days I had unprotected sex Nov 5. Then had light spotting with a bit of cramping Nov 10-11 & 14. Accompanied by 2 days of being super tired and peeing a bit more than usual. Any chance I could be pregnant?
Your irregular periods will make it difficult to pin down your fertile days. If your cycle is not consistent then it will not be easy identify when you’re ovulating and your chances of being pregnant depend on whether you were fertile on or around the date that you had sex. Those symptoms may not indicate a pregnancy but in your case, it is best to take a pregnancy a week after you’ve missed a period just to confirm.
Hello, my cycles are irregular. Haven’t had a cycle since around Labor Day. Just been having mild cramps, spotting, and discharge. I’ve taken a test, but it came out negative (not sure if it was to early or not). What should I do now?
Your period may be delayed for other reasons besides a pregnancy. Your last period was in September – if you were pregnant, then it would show on a pregnancy test by now. You need to see your doctor – “with proper therapy, one’s irregular periods may become regular again.” Read more at this article http://womanjunction.com/irregular-menstrual-cycle-occurs/
Hi, I had my period last month October 18th and had unprotected intercourse with my boyfriend on October 30th. I was supposed to start my period on the 15th of November but I didn’t. Could I be pregnant?
If you have a 28 days cycle, you would have ovulated from October 30 to November 3. Your chances of being pregnant would be quite high.
Hi, you are doing a good job. Pls I saw my period on 10th September , the next one was 21st October, I had sex 8th, 9th and 10th Nov. Could I be pregnant from having sex those days? When is my fertile period? Pls reply
Do you have regular or irregular cycles? How many days are in your cycle? I would need this information in order to respond appropriately. Your chances of being pregnant depend on whether you were fertile on or around the date that you had sex. It is important to know the number of days in your menstrual cycle.
I got my period in Oct 17 and then had sex on the 31 of Oct I have not gotten my period yet what are the chances of being pregnant
Hi, I had a period on July 5-10 I had intercourse on July 21,22,or 23 and started my last period August 1-6 which seemed weird. I’m pregnant now and was wondering did I get pregnant the ending of July or August 15th and I believe I have 27 cycle I think.
Hi. I had my last period Oct 1-5. I was under stress for months since August. Last Oct, I had series of sleepless nights because of work. There was a time in oct where I only slept 1-2 hrs 3 days in a row. I had protected sex on the 17th. Condom only. My partner was lying on his back and started climaxing. After he finished, we found out there was a leak at the base but we believe nothing came into contact with mine. Maybe a little but only external. Then I thought I could get some rest and regain my sleepless nights after but I was again under stress and haven’t had enough rest since my mother was in the hospital since oct 19-nov 5 and I was taking care of her full time. I am 15 days late as of now and many said I lost weight and pale. I took PT three times already since 9th day of delay but the results were the same, negative. I was fatigue for a couple of days earlier but now im better and that’s all I can say. I am regular but in recent months, I was late for 2-5 days. Why am I experiencing this? Am I pregnant? Or the it’s the stress? What should I do? I dont want to be pregnant.
It seems the fatigue and stress are taking a toll on your body and affecting your menstrual cycle. Stress has very powerful effects so it’s best to try and rest any time it is possible. It’s good to know that things have improved so use the time to regain your strength. You menstrual flow will be regulated once you overcome the stressors in your life.
Hi, my period came on 10/25/15 lasted about 4 days. I had sex on 11/5/15 the condom came off. I started my period again on 11/10/15. Very light spotting brownish discharge some pinkish red color. It was like this for about 5 days. Could I be pregnant?
Your chances of being pregnant depend on whether you were fertile on or around the date that you had sex. This was a very irregular cycle – it was approximately 16 days between both periods. To determine if you’re pregnant, it’s best to wait and see if you’ll have another period in November or December
I had my last two periods on 6th and 10th September and Oct respectively, I had unprotected sex thereafter, I haven’t menstruated up till now, could I be pregnant?
You would have an increased chance of being pregnant if you have sex on or around your ovulation days. It is important to know the days in you cycle to provide an accurate response. If you were ovulating when you had unprotected sex then you could be pregnant, if you were not ovulating at that time then the chances would be low.
Hello me and my boyfriend ate trying to have another child I started my period on the 10th of Nov and still on.. I am sure to end within 2 days. I am trying to see when I am ovulating? ? Please and thank you
Ovulation typically occurs 14 days before the start of your menstrual period. If your cycle lasts for 28 days, you can ovulate on the 14th day like the average female. However, you will start ovulating around the 11th day if you have periods 25 days apart. Alternatively, you will not ovulate until the 20th day if your cycles are longer, like for 34 days. If periods are irregular it would be more challenging to determine the fertile days. So when you ovulate it depends on the number of days in your cycle.
Got my menses 18 Oct. My cycle is 28 days. Had sex nearly all the days. Can I be pregnant?
Hi. I’ve had my period 2nd Oct-12th Oct… I’ve had unprotected sex on 16th Oct, I’ve had light spotting on 24th Oct. I’ve had headache, backache, abdominal cramps (light), upset stomach, feeling sick mornings. Its 14th November but I haven’t had my period yet, is it possible that I could be pregnant?
Please help.
Your chances of being pregnant depend on whether you were fertile on or around the date that you had sex. You did not indicate the number of days in your menstrual cycle so it difficult to say if you were fertile when you had sex. Since you have missed a period now is a good time to take a pregnancy test confirm. You can get the most accurate result if you wait at least one week after missing your period. In addition, the result might be even more accurate if the test is done first in the morning as the urine is far more concentrated at this time. The urine-based home pregnancy tests offer great accuracy.
Am I pregnant? We had a sexual intercourse with my boyfriend two weeks probably before my menstrual period but now it is already 6 days delayed. And I can’t help worrying because I experienced nausea since the day before yesterday, the numbers of hours of my sleep increases.
Since you would have already missed your period by at least one week, you can now take a pregnancy test to confirm if you’re truly expecting. You can get the most accurate result if you wait at least one week after missing your period. In addition, the result might be even more accurate if the test is done first in the morning as the urine is far more concentrated at this time. The urine-based home pregnancy tests offer great accuracy.