🩸Blood Type Calculator

Determine possible child blood types based on parents' blood types.

Parent 1

ABO Type

Rh Factor

Parent 2

ABO Type

Rh Factor

Possible Child Blood Types

56%

19%

Rh: 100% positive possible

For educational purposes only. Consult a medical professional for clinical blood typing.

About Blood Type Calculator

Determine all possible blood types a child could inherit based on the ABO and Rh blood types of both parents. Blood type inheritance follows Mendelian genetics, and this calculator shows all possible combinations with their probabilities — useful for educational purposes and satisfying parental curiosity about their child's likely blood type.

How to Use Blood Type Calculator

1
Step 1
Select Parent 1's ABO blood type (A, B, AB, or O) and Rh factor (positive or negative).
2
Step 2
Select Parent 2's ABO blood type and Rh factor.
3
Step 3
View all possible child blood types and the probability of each occurring.

Common Use Cases

Parents curious about which blood types their child could inherit
Biology students studying ABO blood type genetics and Mendelian inheritance
Healthcare educators demonstrating blood type inheritance in genetics lessons
Expecting parents learning about blood compatibility considerations during pregnancy

Frequently Asked Questions

Can blood type testing identify paternity?

Blood type alone cannot confirm paternity but can exclude it — if a child's blood type is impossible given one parent's type, that person cannot be the biological parent. DNA testing is required for conclusive paternity results.

What is the rarest blood type?

AB negative is the rarest blood type, occurring in roughly 1% of the population. AB positive is the universal plasma donor type, while O negative is the universal red blood cell donor.

Is this medically accurate?

The calculator applies standard ABO and Rh Mendelian inheritance rules. Results are for educational reference only and should not replace medical blood typing from a laboratory.