What is the rarest blood type or group in the world (on earth)? Blood is classified into groups using the letters A, B, C and O. In addition, the Rhesus factor characteristic, which can be positive (Rh+) or negative (Rh-) is also marked in the groups. In total there are 8 groups of blood. But which of these blood groups is the rarest and why?
Types of Blood Groups
Rhesus Factor
Occurrence of Blood Groups
| Group | Percentage | Distribution |
| O+ | 37.4% | 1 in every 3 |
| A+ | 35.7% | 1 in every 3 |
| B+ | 8.5% | 1 in every 12 |
| AB+ | 3.4% | 1 in every 29 |
| O- | 6.6% | 1 in every 15 |
| A- | 6.3% | 1 in every 16 |
| B- | 1.5% | 1 in every 67 |
| AB- | 0.6% | 1 in every 167 |
From the chart above, it is clear that the most common blood type is O+. On the other hand, the rarest blood type is AB-.
Rarest Blood Type