Safe Days Calculator

Use safe days calculator to avoid unwanted pregnancy by calculating how many days after the period is safe to avoid pregnancy. It’s free and easy to use.

First day of your last menstrual period (LMP)
Shortest Cycle Length
28 Days
Longest Cycle Length
32 Days

Also Use: Ovulation Calculator, will help you determine your “fertility window”.

Also Use: Due Date Calculator, If you want to know when your precious is coming.

  • Being a responsible, sexually active person is essential if you want to avoid an unplanned pregnancy. If you are not ready to have a baby yet but want to enjoy sexual intercourse, you can do that and still be safe. Safe days are a scientifically tested and proven method of preventing unwanted pregnancies without using any kind of contraception method. 

  • That means no hormones, injections, or drugs in your organism can have various effects on you, including weight gain and extreme mood swings. It is a natural family planning method as it gets, with the lowest risk possible, if properly used. This method will remove any pregnancy scares you might have. 

  • To calculate and plan you're safe days, you first have to know and understand your menstrual cycle. Once you are aware of what is happening in each phase of your cycle, you will be able to precisely calculate the days when it's safe to have sex to prevent conception. 

What is a safe day/infertile period?

Your safe days are those days in the calendar when you have minimal chances to get pregnant if you have sex. This is the "safe window" for those who want to have sex without any kind of protection. During this period, there is not a viable egg present. No egg - no baby. So if you happen to have intercourse, you don't need to be worried. In other words, if you have sex outside your ovulation days, you're good. 

When does ovulation occur?

Ovulation typically occurs approximately 14 days before the start of the next menstrual cycle. To know the exact day is not always possible, though. In the case you have primarily regular periods, you can easily calculate your ovulation days. Simply use the date of your previous menstrual cycle as a starting point. You need to know that an egg can be fertilized by a sperm only four days before and three days after ovulation. To put it simply, days before and post-ovulation are definitely not safe days for sex unless you want to conceive. 

How to calculate your safe days?

To calculate safe days, you first need to understand the different phases of your menstrual cycle. There are three

Safe Period Calculator

  • The follicular phase (pre-ovulation phase)

  • The ovulation phase

  • The luteal phase (post-ovulation)

The duration of each of the phases varies for women, although it is believed that the average menstrual cycle lasts for 28 days. The first day of the bleeding counts as the first day of the new menstrual cycle.

1. The follicular phase

This phase occurs before ovulation and involves the maturing of the follicles in the ovary. This phase ends with ovulation, and the hormone estradiol is working to help the stimulating hormone (FSH) secretion. 

2. The ovulation phase

A mature ovarian follicle ruptures and discharges a viable egg, ready for fertilization. The ovulation phase is often referred to as the time just before and after ovulation. You are likely to get pregnant if you have unprotected sex on the day you're ovulating. 

3. The luteal phase

This phase is the last one in the menstrual cycle, marked by the creation of the corpus luteum. This phase ends in either pregnancy or the degradation of the corpus luteum, a temporary endocrine structure that helps with estrogen and progestogen production. Those are the hormones your body needs to maintain the endometrium.

how many days after period is safe to avoid pregnancy

Safe days after the period

  • If you want to avoid pregnancy, you will be glad to know that you can calculate safe days after your period. The safe days depend on both the lifespan of the sperm and the egg. Ovulation mainly occurs on the 14th day of the menstrual cycle if it's of an average length of 28 days. This calculation is adjusted to reflect WHO data showing that approximately 80 percent of menstrual cycles range between 26 to 32 days. The ovulation period varies from woman to woman. It can happen anywhere from the 12th to the 19th day of the menstrual cycle. 

  • The sperm can live in your reproductive system for up to five days. That means it is possible to conceive from unprotected sex if you had it five days before ovulation, even though the lifespan of a viable egg is only approximately 24 hours. If it's not fertilized in 24 hours, it will die, and it will be safe for you to have sex. 

Safe period calculator really helps

  • In most cases, a cycle calculator will help women determine the safe days of their menstrual cycle. But, you would need to know the date of your periods and your body temperature. Keeping track of your periods for a minimum of six months will help you map out your fertile days. 

  • Important note: If your menstrual cycle is regular 26 do 32 days and the range between your longes and shortest cycle last more than eight days, it is somewhat risky to use the calculator method. Teenagers and women on the verge of menopause should know that the calculator method might not work for them because of their potentially unpredictable cycles. 

How to calculate safe days

Other methods to avoid unwanted pregnancy

If you're not exactly suitable for the safe day calculator method, you can use other fertility awareness methods.

  • tracking your basal body temperature

  • checking cervical mucus

  • using ovulation predictor kits available in drugstores.

Please Note

If you have unprotected sex during the safe period will definitely decrease your chances of getting pregnant. Still, this cannot be taken as a guarantee. Research has shown PUBMED that natural family planning has a 25 percent failure rate. So, if you want to avoid unplanned pregnancy, the safest possible option is to talk to your gynecologist about reliable birth control options for you.


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Frequently asked questions