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





My monthly flow is from Aug 2-4 , pls when will I ovulate to have sex and stand a chance to conceive.
Hi, based on a 28 day cycle your best chance would be from August 12th through the 16th. Good Luck!
Hi my period was supposed to start on the 2nd of Aug that is yesterday but I haven’t seen anything yet I usually have a cycle of 28days. I’m having cramps, sore breasts. Is it too early to take a pregnancy test?
Hi Taylor, if you haven’t seen your period yet, take a pregnancy test.
I saw my period on 5th of July and it came again on 31st of July what could be the cause.
Hi Prisca, that’s normal. It doesn’t seem like your cycle was that short, it only seems like it was about a day or two early.
Hello…pls I had my period on 3rd July, 2019…had sex 12th July took pills next day, supposed to see my period on 30th july now it’s 2nd of August.
Hi Rose, I hope by now (the 10th of August), you’ve gotten your period. Generally, taking the morning after pill that soon does do as it says and prevents pregnancy but can also alter your period because of the added hormones.
I have saw my period on 1 july 2019 when did i expect it again
Hi there, you should have seen it already as of the 1st of August when you posted this question. Sorry for the delay, however if you have’t seen it yet take a pregnancy test if you haven’t yet.
I saw my period on 29 June when do I expect it back
Hi Nola, Based on an average 28 day cycle, you should have seen it around the 27th of July, so at this point you are a bit late.
I gotten my period on May 29th-June 2nd… I was suppose to get my period again from July 1st-July5th but it never came… I’ve taken 6 homes test it said not pregnant and I’m just trying to figure out why my period is delayed.. me and my husband want to have a baby but we don’t know where to start this whole process at.. I’m starting to believe I can not have any children.
Hi DeJenna, if you are having trouble conceiving it could be because you aren’t ovulating regularly. I would recommend making an appointment with your doctor. They can run tests to help determine if there is anything you can do to help your body along to get pregnant or if there is an issue how to correct it. Good Luck.
Hi
I saw my period 27th June and unto now I haven’t see my next period and it’s the 29th july
Hi Jamila, if there is a possibility that you could be pregnant I would take a pregnancy test. If not consider anything that has gone on within the last month such as illness, medications, weight loss or gain, stress, etc. These things can cause your period to be delayed. I would take a pregnancy test honestly.
My cycle is 25 days. Then I was on periods 5-7 July had sex 10 July. Then on periods 23-25 Is that normal?
Hi Michelle, so you didn’t appear to have sex during your fertile period if you are saying your periods are only 3 days, and you got your period a bit early. That can happen sometimes. I would keep an eye on it but if it continues to be shorter I would see your doctor.
My period came on June 30th and went off July 7th…it was suppose to come on July 2nd and go off on july 7th but was not the case now my period suppose to start July 27th is that normal?
Hi Jen, you sent a message before the 27th so that seems normal that you haven’t seen it yet. As of now, the 31st have you gotten your period. If you have then you’re good. If you haven’t then I would recommend waiting a few days then take a pregnancy test.
I had my menses on 29th to 3rd June ,ovulated on 11th June and had sex on 13th June please,is the probability for me to be pregnant high? Thank you.
Hi Maaluzie, if you haven’t had your period yet, then take a pregnancy test because you could, and most likely would, be pregnant.
hi good afternoon, may last period was june 23 it last for 3 days. in june 30 we had unprotected sex, and the next was July 14 unprotected sex also.. and i expect that i will get period last july 21. but it didn’t come ☹️. am i pregnant?or just missed period..? pls reply thanks 😊
Hi Vanessa, a missed/late period in addition to having unprotected sex could mean that you are pregnant. Based on a 28 day cycle though you wouldn’t have been fertile during the timeframe that you had sex but if you have a shorter cycle then it’s quite possible that the 30th was closer to your fertile period. I would take a pregnancy test.
So my period started yesterday the 21st it ends on the 25th could you tell when is the best time to get pregnant
Hi Ariana, the best time based on your period would be from July 30th to August 3rd. Good luck and have fun!
My first day of period was on 14th June and I used a PT with a negative result three days from now. Everytime I wash my own having whitish means and a few days before my expected date of period are in stress. Do u think it is possible to get pregnant or it could be a cause of stress?
Hi Jojie, I’m sorry but I really don’t know what you are asking. Are you having whitish discharge? That could be normal, some women naturally have more discharge than others and right before your period than can be absolutely normal as well. It’s not stress, it’s just your body. As far as getting pregnant this will not prevent you from getting pregnant. In hope I’ve answered your question.
I saw my period on June 25th ,when will I expect it on july
Hi Gift, you should have seen it around the 23rd of July. If you haven’t and you have the possibility of being pregnant, I would recommend a pregnancy test.
I had my last period June 11 and made love with my husband thru June 16- till June 28. Today is July 22 and I still haven’t seen my period. Been having cramping a lot and on July 20 and July 21 when I went to go pee just had stain very little on the paper.
I did a urine pregnancy test on July 20 and was Negative. 😢
Hi Violet, have you taken another pregnancy test since then? I would recommend that. Plus if you are trying to get pregnant and your periods aren’t consistent, I would have a discussion with your doctor. They can do testing to see what is going on and medications to help you ovulate more regularly if necessary. Good luck.