Blood types
You're somebody's type
Pick a blood type to see who it can help and who it can receive from. Share the link with a type picked to show someone their matches.
O- can give to all 8 blood types
Universal red-cell donor. In an emergency, when there is no time to test the patient's type, O- is the blood that is given.
- Gives to
- O- O+ A- A+ B- B+ AB- AB+
- Receives from
- O-
Matches shown are for red blood cells (whole blood). Plasma and platelets follow other rules, and hospitals always cross-match before a transfusion.
The full compatibility chart
Rows are donors, columns are patients. A tick means the donor's red cells can be given to that patient.
| Donor / Patient | O- | O+ | A- | A+ | B- | B+ | AB- | AB+ |
|---|---|---|---|---|---|---|---|---|
| O- | Compatible | Compatible | Compatible | Compatible | Compatible | Compatible | Compatible | Compatible |
| O+ | Not compatible | Compatible | Not compatible | Compatible | Not compatible | Compatible | Not compatible | Compatible |
| A- | Not compatible | Not compatible | Compatible | Compatible | Not compatible | Not compatible | Compatible | Compatible |
| A+ | Not compatible | Not compatible | Not compatible | Compatible | Not compatible | Not compatible | Not compatible | Compatible |
| B- | Not compatible | Not compatible | Not compatible | Not compatible | Compatible | Compatible | Compatible | Compatible |
| B+ | Not compatible | Not compatible | Not compatible | Not compatible | Not compatible | Compatible | Not compatible | Compatible |
| AB- | Not compatible | Not compatible | Not compatible | Not compatible | Not compatible | Not compatible | Compatible | Compatible |
| AB+ | Not compatible | Not compatible | Not compatible | Not compatible | Not compatible | Not compatible | Not compatible | Compatible |
- Compatible
- Not compatible
Three things worth knowing
-
O-
O- is the universal donor
Its red cells can be given to every patient, which is why emergency rooms keep it ready.
Who can it help? -
AB+
AB+ is the universal recipient
A patient with AB+ can receive red cells from any of the 8 blood types.
Who can help it? -
AB
Plasma works the other way round
For plasma, AB is the universal donor and O can only give to O.
More tools that may help
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Can I donate blood today?
Answer a few short questions and see whether you can donate now, and if not, why and when.
-
When can I donate again?
Enter your last donation date and see the day you can donate again.
-
Child’s blood type predictor
Pick both parents’ blood types to see which types the child can and cannot have.
Know your type? Someone near you needs it.
Sign up as a donor and we will tell you when a patient near you needs your blood type.