DayZ Wiki › Guides & tools › Blood type checker
Tool · Medical
Blood type checker
The wrong blood bag kills your friend. Pick the two types and get a straight answer, plus the full chart and the steps to test, collect and transfuse.
Check a pair
Is this transfusion safe?
Full chart
Compatibility chart
| Patient ↓ / Donor → | O- | O+ | A- | A+ | B- | B+ | AB- | AB+ |
|---|---|---|---|---|---|---|---|---|
| O- | ✓ | ✗ | ✗ | ✗ | ✗ | ✗ | ✗ | ✗ |
| O+ | ✓ | ✓ | ✗ | ✗ | ✗ | ✗ | ✗ | ✗ |
| A- | ✓ | ✗ | ✓ | ✗ | ✗ | ✗ | ✗ | ✗ |
| A+ | ✓ | ✓ | ✓ | ✓ | ✗ | ✗ | ✗ | ✗ |
| B- | ✓ | ✗ | ✗ | ✗ | ✓ | ✗ | ✗ | ✗ |
| B+ | ✓ | ✓ | ✗ | ✗ | ✓ | ✓ | ✗ | ✗ |
| AB- | ✓ | ✗ | ✓ | ✗ | ✓ | ✗ | ✓ | ✗ |
| AB+ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
O− is the universal donor: anyone can receive it. AB+ is the universal receiver: they can take any type. Negative types can only receive negative blood.
How to transfuse
Test, collect, transfuse
- Test both people. A blood test kit on the patient and on the donor. Each kit is single use. A blood test kit on yourself shows your type in the inventory from then on.
- Collect. Blood bag kit plus an IV start kit on the donor fills a bag with their type. The donor loses blood, so feed and water them afterwards.
- Transfuse. Blood bag plus IV start kit on the patient. A compatible type restores blood. An incompatible one is fatal.
- Or skip it. A saline bag with an IV start kit works on anyone and is far more common.
More on blood, shock and recovery on the medical page, and every item on med supplies.
Know your type
Know your type before you need it
- Test yourself as soon as you find a kit; your type is fixed for that character.
- In a group, write everyone's type down. One O− player is the group's emergency donor.
- Unknown blood bag? Do not use it. Use saline.
- A blood bag takes the donor's type: note whose blood it is when you fill it.
Quick answers
Questions people ask
What blood type is universal in DayZ?
O− is the universal donor: anyone can receive it. AB+ can receive any type.
What happens if you give the wrong blood type in DayZ?
The patient dies. Always test both people first, or use a saline bag, which works on anyone.
How do you find out your blood type in DayZ?
Use a blood test kit on yourself. Your type then shows in your inventory.
Can O+ give blood to A+ in DayZ?
Yes. O+ can give to O+, A+, B+ and AB+, but not to any negative type.
Keep going
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Last checked 28 October 2026, against DayZ 1.30 (PC 1.30.164200, console 1.87).