Implantation Calculator
When does the fertilized egg actually settle in? The 6-12 day window after ovulation, based on the classic Wilcox study of 1999.
Mostly 14 · leave as-is if unknown
Implantation occurs 6-12 days after ovulation and most commonly on days 8-9 — from Wilcox, Baird & Weinberg, N Engl J Med 1999, still the reference study. Implantation later than day 12 is associated with higher early-loss rates, which is a conversation for a provider, not a calculator.
Questions people ask
Can I feel implantation?
Some people report mild cramps or a day of light spotting about a week after ovulation, but most notice nothing at all. Neither presence nor absence of symptoms tells you whether implantation happened.
When can a test turn positive?
Home tests detect hCG, which rises after implantation — most tests are reliable from the first day of a missed period. Testing earlier risks a false negative even in a healthy pregnancy.