Blood Type Calculator

Predict possible child blood types from parent genetics

Select Parent Blood Types

Parent 1

Parent 2

Select both parents' blood types above to see possible child blood types

ABO Blood Type Inheritance

Blood type is determined by the ABO gene and the Rh factor. The ABO gene has three alleles: IA, IB, and i. Both IA and IB are co-dominant over i (recessive).

Each parent passes one ABO allele and one Rh allele to their child. Since phenotypes (like "type A") can come from multiple genotypes (AA or AO), the calculator shows all possibilities.

Blood TypePossible GenotypesCan Donate ToCan Receive From
AAA or AOA, ABA, O
BBB or BOB, ABB, O
ABABABA, B, AB, O
OOOA, B, AB, OO

Rh factor: Rh+ (positive) is dominant. Two Rh- parents always have Rh- children. An Rh+ parent may carry a recessive Rh- allele, so Rh+ x Rh+ can sometimes produce Rh- children.

Privacy & Limitations

  • All calculations run entirely in your browser -- nothing is sent to any server.
  • Results are estimates and should not replace professional medical advice.

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Blood Type Calculator FAQ

What is Blood Type Calculator?

Blood Type Calculator is a free health tool that helps you Predict possible child blood types from parent blood types.

How do I use Blood Type Calculator?

Enter your input values, review the calculated output, and adjust inputs until you reach the result you need. The result updates in your browser.

Is Blood Type Calculator private?

Yes. Calculations run locally in your browser. Inputs are not uploaded to a server by default, and refreshing the page clears session data.

Does Blood Type Calculator require an account or installation?

No. You can use this tool directly in your browser without sign-up or software installation.

How accurate are results from Blood Type Calculator?

This tool applies standard formulas or deterministic processing logic for estimates. For medical, legal, tax, or investment decisions, verify with a qualified professional.

Can I save or share outputs from Blood Type Calculator?

You can bookmark this page and copy outputs manually. Results are not persisted in your account and are typically not embedded in the URL.

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