Child Blood Type Calculator: ABO & Rh Inheritance Free
Discover which blood types your child could inherit from each parent.
Pick each parent ABO blood group and Rh factor and see which combinations the baby could inherit, per Mendel laws.
By VOV · Last updated: October 21, 2026
How it works
How it works: the possible ABO genotypes of each parent are crossed (O=ii, A=IA_/IAIA, B=IB_/IBIB, AB=IAIB) and resulting groups are listed; for Rh, negative only appears if both parents carry it. Simplified genetic estimate: only a lab test confirms the real type.
Use cases
- Find out which blood types your baby could inherit based on yours and your partner's
- Verify your family's blood-type compatibility before donating blood to a sick relative at the hospital
- Solve the family mystery about why your child has a different blood type than yours
Frequently asked questions
Is the result 100% certain?
No: it is a genetic prediction from the declared types. Rare mutations or uncommon types (like Bombay phenotype) can change it.
Why are there several possible types?
Because a person with group A may be IAIA or IAi; without genetic testing we cannot know, so all possible combinations are listed.
What if parents don't know their Rh?
Rh negative is recessive: if both parents are positive the baby can be positive or negative; if both are negative, it will be negative.