Blood Type Compatibility Calculator and Chart

How to use

1. Pick a recipient type and press Show compatible donors to light up the red-cell grid.
2. Scroll the result for the universal-donor or universal-recipient note.
3. Pick two parent types and press Show child possibilities for the ABO genetics table.
4. Read the plasma note and the clinician disclaimer at the bottom.

General information only — not medical, financial or legal advice. Figures cross-checked against public official sources (IRS / HMRC / NHS / WHO guidance); content last reviewed September 2026. For decisions that matter, confirm with a licensed professional in your country.

About this tool

Blood type compatibility is a fixed reference table, so this page embeds the whole red-cell grid: pick any ABO and Rh recipient type and the compatible donor types light up — from O−, the universal red-cell donor, to AB+, the universal recipient. A second calculator applies standard ABO Mendelian genetics to two parent types and lists the ABO types their child could have, with a plain-language note on how the Rh gene behaves. Plasma is included as a note because it runs the opposite way: AB plasma is the universal plasma donor, and type O recipients can receive plasma from any group. Real transfusion decisions are made by clinicians using antibody screens and crossmatching, because rare subgroups and antibodies exist beyond this chart. It is an educational estimate — not medical advice.

FAQ

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