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Blood Compatibility Guide

Understanding blood type compatibility is crucial for safe blood transfusions. Learn which blood types can safely donate to and receive from each other.

Interactive Charts
Compatibility Checker
Educational Content
O-
O+
A-
A+
B-
B+
AB-
AB+

Compatibility Checker

Select blood types to check donation compatibility

Blood Type Compatibility Checker

Blood Type Compatibility Matrix

Click on any blood type to see compatibility details

O-

Universal Donor
Population: 6.6%
Rare

Can donate to all blood types

Can Donate To:
Can Receive From:
O-

O+

Universal Red Cell Donor
Population: 37.4%
Most Common

Can donate red cells to all positive blood types

Can Donate To:
Can Receive From:
O- O+

A-

A Negative
Population: 6.3%
Rare

Can donate to all A and AB types

Can Donate To:
Can Receive From:
O- A-

A+

A Positive
Population: 35.7%
Common

Second most common blood type

Can Donate To:
Can Receive From:
O- O+ A- A+

B-

B Negative
Population: 1.5%
Very Rare

One of the rarest blood types

Can Donate To:
Can Receive From:
O- B-

B+

B Positive
Population: 8.5%
Less Common

Less common but valuable for transfusions

Can Donate To:
Can Receive From:
O- O+ B- B+

AB-

AB Negative
Population: 0.6%
Extremely Rare

Rarest blood type, universal plasma donor

Can Donate To:
Can Receive From:
O- A- B- AB-

AB+

Universal Recipient
Population: 3.4%
Rare

Can receive from all blood types

Can Donate To:
Can Receive From:
O- O+ A- A+ B- B+ AB- AB+

Special Compatibility Rules

Important exceptions and special considerations

Emergency Transfusion

In life-threatening emergencies when blood typing is not possible, O- blood (universal donor) can be given to anyone.

Rh Factor in Pregnancy

Rh-negative mothers carrying Rh-positive babies need special monitoring and RhoGAM injections.

Plasma Compatibility

Plasma compatibility is opposite to red blood cell compatibility. AB+ is the universal plasma donor.

Platelet Compatibility

Platelets are generally given to recipients of the same ABO group, but cross-matching is less critical.

Understanding Rh Factor

The Rh factor is a protein found on red blood cells. People are either Rh-positive (have the protein) or Rh-negative (don't have the protein).

Rh Positive (+)

Can receive Rh+ or Rh- blood of the same ABO group

Rh Negative (-)

Can only receive Rh- blood of compatible ABO groups

Important Note

About 85% of people are Rh-positive. Rh-negative individuals should only receive Rh-negative blood to prevent antibody formation.

+
Rh Positive

Has Rh protein

-
Rh Negative

No Rh protein

Quick Reference Table

Complete compatibility chart for all blood types

Blood Type Can Donate To Can Receive From Population % Frequency
O- O- O+ A- A+ B- B+ AB- AB+ O- 6.6% Rare
O+ O+ A+ B+ AB+ O- O+ 37.4% Most Common
A- A- A+ AB- AB+ O- A- 6.3% Rare
A+ A+ AB+ O- O+ A- A+ 35.7% Common
B- B- B+ AB- AB+ O- B- 1.5% Very Rare
B+ B+ AB+ O- O+ B- B+ 8.5% Less Common
AB- AB- AB+ O- A- B- AB- 0.6% Extremely Rare
AB+ AB+ O- O+ A- A+ B- B+ AB- AB+ 3.4% Rare

Frequently Asked Questions

Common questions about blood compatibility

Blood compatibility is crucial because incompatible blood transfusions can cause serious reactions, including hemolytic reactions that can be life-threatening. The immune system will attack incompatible blood cells, leading to complications.

Incompatible blood transfusions can cause hemolytic reactions where the recipient's immune system attacks the donor's red blood cells. This can lead to fever, chills, kidney failure, and in severe cases, death. This is why proper blood typing and cross-matching are essential.

Yes, O- is called the "universal donor" because it can be safely given to people with any blood type. This makes O- blood extremely valuable, especially in emergency situations when there's no time to determine the patient's blood type.

Yes, AB+ is called the "universal recipient" because people with AB+ blood can receive red blood cells from any blood type. However, they can only donate to other AB+ recipients. AB+ individuals are also universal plasma donors.

The Rh factor is a protein found on red blood cells. People are either Rh-positive (have the protein) or Rh-negative (don't have it). Rh-negative people can only receive Rh-negative blood, while Rh-positive people can receive either Rh-positive or Rh-negative blood of the same ABO group.

Yes, plasma compatibility is opposite to red blood cell compatibility. AB+ is the universal plasma donor (can donate plasma to anyone), while AB- can receive plasma from anyone. This is because plasma contains antibodies that must be compatible with the recipient's red blood cells.

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