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Blood compatibility checker.
Who can donate to whom? Select the patient's blood group and the component needed — the answer changes for red cells vs plasma.
This is a guide, not a medical decision.Hospitals run a crossmatch test on the actual units before any transfusion — compatibility on paper is never the final word. In an emergency, the hospital blood centre decides.
The rules in one breath
Red cells
O− gives to everyone (universal red-cell donor). AB+ receives from everyone (universal red-cell recipient). Otherwise: the patient's Rh sign must match or be negative, and the patient's letter must accept the donor's letter.
Plasma — the mirror image
AB is the universal plasma donor. O receives plasma from everyone. That is why plasma compatibility reads like red-cell compatibility reversed.
Need a real donor in Assam?
Our donor directory lists verified voluntary donors by group and district — message them directly on WhatsApp. Or post a request and every matching donor gets alerted.