Blood Type Calculator
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Blood Type Calculator
ABO, Rh, transfusion compatibility and possible parent–child combinations
Parent 1
Parent 2
Results
Note: Results follow standard ABO and Rh inheritance. Rare exceptions exist, so treat this as a guide rather than a diagnosis.
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This tool allows you to easily check the probable blood groups of a child based on the parents' data, check possible groups of parents for a given child and verify the compatibility of blood transfusions. Thanks to this, the calculator is a practical educational and information support, not only for pupils and students, but also for anyone interested in human biology.
Who is this calculator for
The tool is useful for:
- parents who want to find out what blood types their child may have,
- pupils and students learning about the ABO and Rh systems,
- people who want to quickly check transfusion compatibility,
- anyone who wants to better understand the genetics of blood inheritance.
How to use the calculator
- Select mode:Child, ParentsorTransfusion.
- In "Child" mode, enter the ABO groups and Rh factor of both parents.
- In "Parents" mode, enter your child's ABO and Rh group to see what parent sets are possible.
- In "Transfusion" mode, select the recipient's and donor's blood type to check compatibility.
- ClickCalculateto see the result in an easy-to-read table.
How it works
The calculator uses the basic principles of ABO genetics and the Rh factor. The child's blood group depends on the combination of the parents' alleles: A, B and O. The Rh factor is inherited dominantly, so Rh+ may hide the Rh− allele. The tool considers all possible combinations and returns the child's likely groups. In the case of a transfusion, it checks the compatibility rules: 0− blood as a universal donor, AB+ as a universal recipient, and the rules for other combinations.
Usage examples
Example 1: Parents A+ and B−
A child may be group A, B, AB or 0, and Rh positive or negative depending on the gene combination.
Example 2: Parents 0− and 0+
A child can only have group 0, and Rh depends on the presence of a positive allele.
Example 3: Transfusion, recipient A+, donor 0−
Full compliance. 0− is a safe donor for all groups.
Indicative inheritance table ABO
| Parents | Possible groups of the child |
|---|---|
| A × A | A or 0 |
| A × B | A, B, AB or 0 |
| A × 0 | A or 0 |
| B × B | B or 0 |
| B × 0 | B or 0 |
| 0 × 0 | 0 |
| AB × AB | A, B or AB |
| AB × 0 | A or B |
Why is it worth using the calculator
- You can quickly check the probability of your child's group.
- You can easily verify blood compatibility during transfusion.
- A great educational tool for learning biology and genetics.
- Simple operation, clear results.
FAQ
Is the result certain?
The calculator shows possible groups based on genetics, but will not replace laboratory testing.
Can you predict your exact Rh?
Only partially. If both parents are Rh−, the child will be Rh−. In other cases, the calculator shows both variants.
Can AB have a child with group 0?
No. The combination of AB × AB or AB × 0 will never result in group 0.
Is the result sufficient for medical decisions?
No. The calculator is educational. Blood tests in the laboratory are used for transfusions or diagnostics.
Most common errors
- Confusing the designation A with AB.
- Assumption that Rh+ always means Rh+ in the child.
- Treating the calculator as a substitute for a laboratory test.