Different Blood Types Explained

Why are there different blood types? How can I learn my blood type? From A to O, all your blood type questions answered.

Facts About Different Blood Types


Every year in the United States, 4.5 million lives are saved by blood transfusions from donors just like you. But do you know your blood type? Do you know where blood types come from?   

Learn more about how your blood type is determined; get fascinating facts about each blood type; and get answers and insights to some of the most frequently asked questions about blood types from our medical experts.

No matter what blood type you have – A positive, A negative, B positive, B negative, AB positive, AB negative, O positive, O negative, or a rare and uncommon blood type – we guarantee you’re someone’s type!

 
A Blood Type
Are you type A+ or A-? Learn the facts about what makes your blood type special!
 
B Blood Type
Are you type B+ or B-? Learn the facts about what makes your blood type special!
 
AB Blood Type
Are you type AB+ or AB-? Learn the facts about what makes your blood type special!
 
O Blood Type
Are you type O+ or O-? Learn the facts about what makes your blood type special!
 
Rare and Uncommon Blood Types
Learn about rare and uncommon blood types, including the correlation between blood type and ethnicity and what blood types help patients with sickle cell.
 

Every day, patients in your community need blood transfusions to survive and thrive. They rely on the generosity of donors like you, who help ensure a safe, healthy blood supply. Make an appointment to donate blood today.

Explore donation opportunities in Illinois, Indiana, Michigan, and Ohio.

 
Blood Donation Locations
Find a Versiti blood donation center and search for a blood drive near you. Make an appointment to donate blood today.
 
Host A Blood Drive
Blood drive organizations save lives. Learn how to host a blood drive in your community with Versiti.
 
Types of Donations
Volunteer to donate blood at a blood donation center near you. Find out how often you can donate blood and make an appointment to donate today.
 
Ro Blood Type
Volunteer to donate Ro blood type at a blood donation center near you. Learn how rare Ro blood is and make an appointment to donate Ro blood today.
 
Importance of Diverse Donors
Diverse blood donations improve blood transfusion outcomes for sickle cell patients and diverse blood recipients. Make an appointment to donate blood.

Yes, animals have blood groups! The proteins and antigens that determine an animal's blood group are specific to each species, however, and are therefore not compatible with humans.

Scientific data on blood types and coronavirus continues to evolve. Versiti is staying on top of evolving COVID-19 updates and keeping our donors and staff safe. We encourage our donors to follow CDC guidance. Learn more about Versiti's coronavirus information.

Positive and negative blood types explained: Within your blood group, there’s also a protein called RhD which determines whether your blood type is positive or negative. If you have the RhD protein you’re positive; if you don’t, you’re Rh negative.

There are 4 main blood groups: A, B, AB, and O. Besides these common blood groups, there are over 35 other blood groups and over 600 other known antigens.

Platelets are a component of blood that promotes clotting. They are named after their plate-like shape, and when activated, platelets develop sticky spikes that help them cluster together to seal off cuts and other wounds. Platelets are body’s natural bandages!

A, B, AB, and O. Group O have no ABO specific sugar, while A, B and AB do!

​​​​​​Your blood type will determine what blood you can receive if you ever need a transfusion. If your matched blood type is available, you can safely receive it. For example, an A positive hospital patient can safely receive a transfusion of A positive red blood cells; an O positive patient can receive O positive red blood cells; and so on.

AB positive blood is the universal recipient of red blood cells, meaning a patient with this blood type can safely receive any blood type in an emergency.

“How do I know what blood type I have?” you might be asking. Or: “If I don’t know my blood type, how do I learn?” If you don’t know your blood type, simply donate blood and we will tell you after your first successful donation!

Plasma is a liquid part of blood that carries proteins, hormones and other nutrients throughout the body. It is the biggest blood component, making up 55% of your total blood volume. A healthy supply of plasma in the body:

  • Protects from infection
  • Helps maintain a healthy blood pressure
  • Promotes clotting when you get a cut

Rh incompatibility during pregnancy is when a woman has Rh-negative blood and her baby has Rh-positive blood. In some cases, the pregnant woman's body can react to the baby's blood as a foreign substance and create antibodies that attack the baby's red blood cells and result in a loss of oxygen and death in the baby. Prenatal screening and medical care can help prevent and treat this condition.

The Rh-null blood type, which contains zero Rh antigents, is sometimes called "the golden blood type." Less than 50 people are known to have Rh-null blood, making it one of the rarest blood types in the world. Learn more about rare blood.

You might have heard of a “universal donor” or a “universal blood type.” What is it? A group O negative donor is the universal red blood cell donor, because there are no A or B specific sugars and no Rh protein. Group O negative blood is the universal blood type that can be given safely to any patient in an emergency.

Group AB plasma is the universal plasma donor (because no antibodies to A or B) that can be given safely to any patient.

​​​​​​Your blood type is determined by what you inherit from your biological parents.

The reason we need to match is because of antibodies! You automatically make antibodies to the blood group sugar you don’t have. Group O have antibodies to A and B sugars, group A have antibodies to B, group B have antibodies to A, and AB don’t have any blood group antibodies.
 
Become an Organ and Tissue Donor
Learn more about how to sign up as an organ, tissue and eye donor and how organ donation saves and enhances lives in our communities.
 
Financial Giving
Versiti Blood Research Institute Foundation accepts financial and philanthropic gifts from donors, which helps to propel lifesaving research.
 
Volunteering with Versiti
Versiti volunteers provide an invaluable service to our lifesaving mission. Learn more about Versiti’s volunteer services and how you can serve your community.
 
Blood Donation FAQs
Read frequently asked questions involving donor eligibility, donation process, blood safety and more.
 
Beacon Club Loyalty Program
Blood donors of all blood types and blood drive hosts earn rewards in Versiti’s blood center loyalty club. Donate blood or host a blood drive for rewards.
 
Leaders For Life
Reward your student leaders for saving lives through blood donation.
 
Share Your Story
Versiti invites you to share your story and photo to help encourage more people to give back. You may even be featured throughout the year on our social media.