Blood Donation Eligibility Calculator
Check if you meet the basic requirements for blood donation based on age, weight, health status, and recent activities.
Blood donation eligibility is determined by a set of criteria established by organizations such as the American Red Cross, AABB, and equivalent bodies worldwide. These criteria exist to protect both the donor and the recipient. This calculator provides a general pre-screening — final eligibility is always determined by the blood bank staff on the day of donation.
Basic Requirements for Whole Blood Donation:
| Criteria | Requirement |
|---|---|
| Age | 17+ years (16 with parental consent in some regions) |
| Weight | At least 110 lbs (50 kg) |
| Hemoglobin | Female: 12.5 g/dL minimum. Male: 13.0 g/dL minimum |
| Health | Generally healthy, feeling well on day of donation |
| Time since last donation | Whole blood: 56 days (8 weeks). Platelets: 7 days. Plasma: 28 days |
Common Temporary Deferrals:
- Tattoo or piercing: 3–12 months depending on location and regulation
- Travel to malaria-endemic areas: 3–12 months after return
- Recent illness (cold, flu): Until fully recovered, typically 7–14 days
- Antibiotics: Until course is completed and infection is resolved
- Surgery: 6–12 months depending on type
- Pregnancy: 6 weeks after delivery
- Vaccination: Varies by vaccine type (0–14 days for most, 2 weeks for live vaccines)
Donation Types and Frequency:
| Type | Frequency | Duration | Volume |
|---|---|---|---|
| Whole blood | Every 56 days | 8–10 minutes | 1 pint (~470 mL) |
| Platelets (apheresis) | Every 7 days (max 24/year) | 1.5–2.5 hours | Platelets only |
| Plasma | Every 28 days | 1–1.5 hours | Plasma only |
| Double red cells | Every 112 days | 30 minutes | 2 units red cells |
Weight and Blood Volume: Your total blood volume is approximately 70 mL per kilogram of body weight (or about 1 pint per 14 lbs). The minimum weight requirement of 110 lbs (50 kg) ensures that donating one pint represents a safe proportion of your total blood volume — roughly 10–13% for someone at the minimum weight. Larger donors tolerate blood loss more easily.
After Donation Tips: Drink extra fluids for the next 24–48 hours. Avoid heavy lifting or strenuous exercise for 24 hours. Eat iron-rich foods (red meat, spinach, beans, fortified cereals) to help replenish iron stores. Your body replaces the fluid volume within 24 hours, but red blood cells take 4–8 weeks to fully regenerate, which is why the 56-day waiting period exists.
One Donation Can Save Up to Three Lives: Whole blood is separated into red cells, platelets, and plasma — each component can help a different patient. Regular donors are the backbone of the blood supply, and demand is constant.