Blood Donor Calculator

Your details

Choose the type of donation you made or plan to make. Each type has a different waiting period.
The date of your most recent donation of this type. Leave blank if you have never donated.
Used to calculate total blood volume via the Nadler formula. Some organisations also apply longer inter-donation intervals for female donors.
Used with weight to estimate your total blood volume (Nadler formula). Optional.
cm
You must weigh at least 50 kg (110 lb) to donate whole blood.
kg
Select your ABO/Rh blood type to see compatibility and universal donor/recipient status.
Minimum donation age is 16-18 depending on your country. The standard upper limit is 65 in many countries, though many accept healthy older donors.
years
Next eligible donation dateEligible to donate now
May 12, 2026

The earliest date you can donate again based on your last donation and type

Days until eligible0days
Required wait period56days
Max donations per year6
Lives potentially saved per year18
Estimated total blood volume4.98L
Donation as % of blood volume9%
Blood volume recoveryPlasma volume: 24-48 hours. Red blood cells: 4-6 weeks.
Eligibility statusLikely eligible based on age and weight (subject to health screening on donation day)
Whole blood: can donate toO+, A+, B+, AB+
Plasma: can donate toO+, O-
Whole blood: can receive fromO-, O+
0 days remaining
  • Eligible now
  • Platelets OK
  • Plasma OK
  • Whole blood OK
  • Power Red OK

You are eligible to donate today.

  • You are eligible to donate whole blood right now.
  • By donating the maximum 6 times per year, you could help up to 18 people.
  • Your estimated total blood volume is 4.98 L. A single whole blood donation represents about 9.0% of that, a safe and quickly replenished amount.

Next stepFind your nearest donation centre and book an appointment. Drink plenty of water and eat a good meal before you go.

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