What is implantation?
Implantation is when a fertilized egg attaches to the lining of your uterus, this is the official start of pregnancy. This process typically happens between 6 to 10 days after ovulation, though the exact timing varies from person to person.
Most people don't feel implantation happening, but knowing your implantation window can help you plan when to take a pregnancy test for the most accurate results.
How to use the implantation calculator
Using Lively's implantation calculator is simple. You'll need either:
- Your ovulation date (if you track your cycle), OR
- The first day of your last period
Enter one of these dates, and the calculator will estimate a window of when implantation might have occurred. Remember, this is an estimate, implantation timing varies based on your unique cycle and when fertilization actually happened.
How do you know if implantation was successful?
After ovulation, an egg remains viable for about 24 hours. If it meets sperm during this window and gets fertilized, it travels through your fallopian tube to your uterus, where it implants into the uterine lining 6-10 days later.
Possible signs of implantation
Some people report noticing subtle signs around the time of implantation, including:
- Implantation bleeding: Light spotting or pink/brown discharge around 1-2 weeks after conception.
- Mild cramping: Some people feel light cramping similar to period cramps, but gentler.
Important note
Many people experience no symptoms at all during implantation. The only reliable way to confirm pregnancy is with a pregnancy test taken after a missed period.
When can you take a pregnancy test after implantation?
For the most accurate results, wait until the day your expected period is due, or even a few days after, before taking a pregnancy test.
Why wait?
Home pregnancy tests detect human chorionic gonadotropin (hCG), a hormone your body starts producing after implantation. However, hCG levels need time to build up to detectable levels:
- On the first day of a missed period: Tests are about 90% accurate
- One week after a missed period: Accuracy increases to about 97%
Pro tip: Use Lively's pregnancy test calculator to find the optimal testing window based on your cycle.
Key takeaways
- Implantation typically occurs 6-10 days after ovulation
- Knowing your implantation window helps you determine the best time to take a pregnancy test
- Implantation calculators provide an estimated window, not an exact date
- Most people don't feel implantation happening, and that's completely normal
- For the most accurate pregnancy test, wait until your period is due or a few days after
- Track your cycle with the Lively app to better understand your ovulation, fertile window, and pregnancy planning


