Blood Type Compatibility Calculator
Find out who you can donate blood to and receive blood from based on your blood type.
Includes Rh factor compatibility.
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Blood Compatibility
Blood type compatibility determines who can safely donate to and receive blood from whom.
ABO + Rh system: There are 8 main blood types: A+, A-, B+, B-, AB+, AB-, O+, O-
Key rules:
- O- is the universal donor (can give to anyone)
- AB+ is the universal recipient (can receive from anyone)
- Rh- can donate to both Rh+ and Rh- of compatible ABO types
- Rh+ can only donate to Rh+ recipients
Blood type distribution (US):
- O+: 38% | O-: 7%
- A+: 34% | A-: 6%
- B+: 9% | B-: 2%
- AB+: 3% | AB-: 1%
Why it matters: Receiving incompatible blood can cause a life-threatening immune reaction. Always verify blood type before transfusion.