Blood Type Compatibility Checker
Check whether a specific donor and recipient blood type combination is compatible using the standard ABO and Rh compatibility rules, or view all compatible donors or recipients for a type.
O- → AB+: Compatible
How to Use the Blood Type Compatibility Checker
Select a donor blood type and a recipient blood type to see whether that specific donation would be compatible, using the standard published ABO and Rh compatibility rules. O- is the universal donor (compatible with all eight types), AB+ is the universal recipient (can receive from all eight types), and Rh-negative blood can only donate to Rh-negative recipients within the negative-to-negative rule alongside the matching Rh-positive group. You can also switch modes to see every compatible recipient for a chosen donor, or every compatible donor for a chosen recipient.
Example
An O- donor is compatible with an AB+ recipient (O- can donate to anyone), but an A+ donor is NOT compatible with a B- recipient, since the ABO groups don't match and B- can only receive from B- or O- blood.
Common Use Cases
- Learning the standard ABO and Rh blood donation compatibility rules for a class or exam.
- Quickly checking whether a specific donor-to-recipient pairing is theoretically compatible.
- Seeing the full list of blood types a given type can donate to or receive from.
FAQs
- Is this a substitute for real medical blood typing? No — this tool is for general education only. Any real blood transfusion requires laboratory blood typing and cross-matching performed by qualified medical professionals before it can be considered safe; never use this tool as a substitute for that process.
- Why is O- called the "universal donor"? O- red blood cells carry neither A nor B antigens nor the Rh factor, so they're far less likely to trigger an immune reaction in a recipient of any other blood type, making O- compatible with all eight types as a donor.
- Why is AB+ called the "universal recipient"? AB+ red blood cells already carry A, B, and Rh antigens, so an AB+ recipient's immune system doesn't react against any of those antigens arriving from a donor, allowing AB+ patients to receive blood from all eight types.