Check a simplified ABO/Rh red-cell compatibility list or an ABO-only plasma compatibility list for donation and receiving directions.
Compatibility lookup
Choose a component and blood type
Educational reference
Compatibility summary
Simplified compatibility estimate
Compatibility information will appear here
Choose donate or receive, a component, and the known blood type.
Compatibility estimateComponent-specific ABO/Rh lookup; plasma lookup uses ABO group only
Compatibility result
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This simplified list is not a donation authorization or transfusion recommendation. It does not account for all red-cell antigens, antibodies, product handling, or clinical context. Ask a blood service or transfusion professional about real donation or transfusion decisions.
Blood-component compatibility depends on which component is being considered and whether someone is donating or receiving it. This page offers a simplified red-cell lookup using ABO group and the positive or negative Rh label, plus an ABO-only plasma lookup that does not use Rh. It does not assess donor eligibility or perform laboratory compatibility testing.
The “blood” option represents red cells, not whole blood. Both tables are educational simplifications: they do not include every antigen, product-specific factor or laboratory result. Do not use a returned list to authorize a donation, select a product or decide that a transfusion is safe.
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How to Use This Calculator
For an educational lookup, select whether you want to donate or receive. Select blood or plasma, then choose the stated blood type. Review all three inputs before calculating. A donate list and a receive list answer opposite directional questions, even for the same person.
Read the component name and direction with the returned groups. The number of groups in a list is not a measure of how useful or valuable a donation is. A blood service can advise on its actual collection needs and the donor’s eligibility.
If your blood type is unknown, obtain an appropriate test rather than guessing from family members or a prior informal calculation. The page has no mechanism to establish the group. It also cannot check a particular blood unit, antibody screen, crossmatch or recipient identity.
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Formula Used
No numerical equation is used. The backend selects a stored list from component × donate/receive direction × blood type. The red-cell table uses all 8 ABO/Rh groups; the plasma table uses the 4 ABO groups and ignores Rh.
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Variables Explained
Input
Unit or choice
Meaning
I want to...
Donate/Receive
Direction of the lookup.
Component
Red blood cells/Plasma
Chooses the red-cell or ABO-only plasma table; the red-cell result is not whole-blood compatibility.
My blood type
ABO/Rh group
Selected type; Rh is not used in the plasma lookup.
I want to... determines direction. For donate, your selected type is treated as the source and the output lists recipient types in the table. For receive, your selected type is the recipient and the output lists donor types.
The component determines which lookup table is used. Red cells and plasma have different compatibility patterns. The plasma list is simplified to ABO groups only and does not account for Rh or other compatibility considerations.
My blood type is one of O−, O+, A−, A+, B−, B+, AB− or AB+. The ABO letters and Rh sign describe distinct aspects of the group. Even those labels do not cover every antigen or compatibility consideration encountered by a transfusion laboratory.
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Worked Example
In the simplified red-cell table, choosing A+ and receive returns O−, O+, A− and A+. Choosing A+ and donate returns A+ and AB+. The difference demonstrates why reversing direction is not a cosmetic change.
Choosing O− and donate in that branch returns all eight listed groups, corresponding to the familiar broad red-cell-donor shorthand. That does not establish universal whole-blood or plasma compatibility, and it does not remove testing requirements.
In the ABO-only plasma table, AB may donate plasma to O, A, B and AB groups, while a person with group O may receive plasma from all four ABO groups in this simplified model. Rh is ignored for this lookup. These examples do not establish compatibility of a particular product or replace transfusion-service procedures.
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Why Use This Calculator?
Use the page to understand the structure of a compatibility lookup and why direction and component matter. Cross-check educational compatibility information with a blood service rather than treating this implementation as a reference standard.
The Red Cross distinction betweenO-negative red cells andAB plasma illustrates the main component difference. Antigens on donor red cells and antibodies in donor plasma are different considerations. A broad donor label for one component cannot be transferred automatically to another.
Actual transfusion decisions involve product-specific procedures, laboratory findings and the clinical situation. The form has no fields for an antibody screen, previous transfusions, pregnancy history or a crossmatch. It does not establish whether any particular donor unit and recipient are compatible, even when their ABO/Rh labels fit a simplified pattern.
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Common Mistakes
Do not call the red-cell branch a complete whole-blood compatibility assessment. Do not treat the ABO-only plasma lookup as a complete compatibility check. Do not confuse compatibility with permission to donate: donation screening can involve health history, timing and collection-service requirements not present here.
An omitted group or a listed group is not clinical authorization. If the purpose is an actual donation or transfusion question, ask the responsible blood service or clinical team to establish the appropriate next step.
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Frequently Asked Questions
Does this tell me whether I am eligible to donate?
No. It only selects a compatibility list from the entered type and component. Eligibility involves separate collection-service screening, which the form does not perform.
Why do red-cell and plasma patterns differ?
They concern different parts of blood. Red-cell antigens and plasma antibodies create different ABO considerations. A universal red-cell donor shorthand therefore does not imply universal plasma donation.
How does the plasma lookup handle blood type?
It uses ABO groups only and ignores Rh. It is an educational simplification, not a validated product-specific compatibility decision or a replacement for transfusion-service testing.
Does O-negative mean universal for every component?
No. The common universal-donor shorthand concerns red cells. AB is the universal ABO plasma donor in the simplified model. Whole blood and other products require their own product-specific considerations.
Can this replace a crossmatch?
No. A group-based lookup cannot test a particular donor unit against a particular recipient or account for all relevant antibodies. Actual compatibility is established through the transfusion service’s procedures.