--- title: When Did I Conceive? description: While there’s no hard science to find the absolute moment of conception, there are a few ways that can help you determine when you conceived. image: https://chariscenter.org/hubfs/Imported_Blog_Media/When%20did%20I%20conceive.jpg --- [Skip to Content](https://chariscenter.org/helpful-advice/when-did-i-conceive#main-content) - [Call | (580) 786-6000](tel:+15807866000) - [Text 24/7 | (580) 441-5611](sms:+15804415611) [![newcharislogo](https://chariscenter.org/hubfs/newcharislogo.png "newcharislogo")](https://chariscenter.org) - [Home](https://chariscenter.org) - Show submenu for Services Services - [Text Our Nurses](https://chariscenter.org/nurse-chat) - [Pre-Abortion Screening](https://chariscenter.org/abortionscreening) - [Pregnancy Tests](https://chariscenter.org/pregnancy-tests) - [Ultrasounds](https://chariscenter.org/ultrasound) - [Abortion Pill Reversal](https://chariscenter.org/abortion-pill-reversal) - [Parenting Services](https://chariscenter.org/services) - [Support Services](https://chariscenter.org/support-services) - [Support for Men](https://chariscenter.org/for-men) - Show submenu for FAQs FAQs - [First Appointment Expectations](https://chariscenter.org/what-to-expect) - [About Pregnancy](https://chariscenter.org/pregnancy-faqs) - [About Abortion](https://chariscenter.org/abortion-faqs) - [About the Abortion Pill](https://chariscenter.org/abortion-pill-faqs) - [Helpful Advice](https://chariscenter.org/helpful-advice) - Show submenu for Support Us Support Us - [Donor Information](https://chariscenter.org/donors) - [Give Now](https://charis.churchcenter.com/giving) - Search - [Make Appointment](https://chariscenter.org/make-appointment) - [Home](https://chariscenter.org) - Show submenu for Services Services - [Text Our Nurses](https://chariscenter.org/nurse-chat) - [Pre-Abortion Screening](https://chariscenter.org/abortionscreening) - [Pregnancy Tests](https://chariscenter.org/pregnancy-tests) - [Ultrasounds](https://chariscenter.org/ultrasound) - [Abortion Pill Reversal](https://chariscenter.org/abortion-pill-reversal) - [Parenting Services](https://chariscenter.org/services) - [Support Services](https://chariscenter.org/support-services) - [Support for Men](https://chariscenter.org/for-men) - Show submenu for FAQs FAQs - [First Appointment Expectations](https://chariscenter.org/what-to-expect) - [About Pregnancy](https://chariscenter.org/pregnancy-faqs) - [About Abortion](https://chariscenter.org/abortion-faqs) - [About the Abortion Pill](https://chariscenter.org/abortion-pill-faqs) - [Helpful Advice](https://chariscenter.org/helpful-advice) - Show submenu for Support Us Support Us - [Donor Information](https://chariscenter.org/donors) - [Give Now](https://charis.churchcenter.com/giving) - [Make Appointment](https://chariscenter.org/make-appointment) - Search # When Did I Conceive? [Pregnancy](https://chariscenter.org/helpful-advice/tag/pregnancy) | [Conception](https://chariscenter.org/helpful-advice/tag/conception) ![When Did I Conceive?](https://chariscenter.org/hubfs/Imported_Blog_Media/When%20did%20I%20conceive.jpg) So, you’re pregnant. But on what date did you conceive, and how can you know who the father is? Need answers now? Chat anonymously with a nurse for free 24/7 at [(580) 441-5611](sms:+15804415611) While there’s no hard science to find the absolute moment of conception, like with your period, there are timed rhythms and cycles that can help you determine – with close proximation – when you conceived. ## What Date Did I Conceive? Whether you’re two weeks or 20 weeks into your pregnancy, there’s some simple math you can perform to confidently know around the time you conceived.  On average, **there are two-to-three days when you ovulate** – the time when your body can get pregnant – each menstrual cycle. This occurs **about two weeks after your last period started**.   ##### Conception Date Calculator By calculating the time since your last period, you can get a rough idea of your ovulation window (when you might have conceived). There are free online calculators to help like the one below, or you can **give us a text at [(580) 441-5611.](sms:+15804415611)** Again, *this is just a rough approximation*. It’s important to remember that each woman’s menstrual cycle and ovulation window are different. Some ovulate for longer periods of time than others, and some have theirs earlier or later during their menstrual cycle. Additionally, sometimes sex before the ovulation window begins can still lead to pregnancy. That is because sperm can survive for up to five days, meaning pre-ovulation sperm can still fertilize an egg if it lasts long enough.1, 2   ##### Conception Calculator First Day of Your Last Period: Average Length of Cycles: Calculate     ##### Conception Date from Ultrasound Another way to determine the conception date is through an ultrasound. Fetuses tend to grow at a consistent rate, which means the age of the fetus can, quite literally, be measured. As such, **an ultrasound can give a more accurate date range than an ovulation calculator**. Having an ultrasound not only helps you know when you conceived but can also confirm the health and viability of the fetus, ensuring that the pregnancy has not miscarried and is not ectopic.3 You can have an ultrasound performed at your local OBGYN office, however, there’s usually paperwork and billing involved. Alternatively, your local pregnancy center may be able to offer [**free ultrasound services**](https://chariscenter.org/ultrasound) without the need for hospitals or insurance companies to get involved.   ##### Get Help Determining Your Conception Date If you need help figuring out which day you conceived or if you have any questions about pregnancy in general, we’re here to help. Simply **send a text to [(580) 441-5611](sms:+15804415611)** and talk to a certified nurse to answer any questions you might have and walk you through your options.   Sources: 1\. https://www.mayoclinic.org/healthy-lifestyle/getting-pregnant/expert-answers/ovulation-signs/faq-20058000 2\. https://my.clevelandclinic.org/health/articles/23439-ovulation 3\. https://my.clevelandclinic.org/health/diagnostics/9704-ultrasound-in-pregnancy   ![newcharislogo](https://chariscenter.org/hs-fs/hubfs/newcharislogo.png?width=200&height=70&name=newcharislogo.png) ##### Get In Touch - [Contact Us](https://chariscenter.org/contact) - [(580) 786-6000](tel:+15807866000) - [For Donors](https://chariscenter.org/donors) ##### Visit Us 1700 W Jones Ave. Duncan, OK 73533 [Get Directions](https://maps.app.goo.gl/KVUKPcM5Ke5MEvhL8) ##### Hours Monday: 9am-5pm Tuesday: 9am-5pm Wednesday: 9am-1pm Thursday: 9am-5pm Friday & Saturday: By appointment only ##### **Here For You** Charis Center doesn’t provide or refer for abortions. Our free services help supply the information needed to understand abortion procedures, potential risks, and side effects.   [Make Appointment](https://chariscenter.org/make-appointment) © 2026 Charis Center. 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