Blood Donation Interval Calculator
Find the earliest dates you can next donate whole blood or platelets after your last donation.
Recent
Formula
How the calculation works
The calculator takes the date of your last donation and adds ninety days to give the next whole blood date.
It adds fourteen days to the same date to give the next platelet donation date, which recovers much faster.
It also shows whether your reference date already falls on or after each eligible date.
Common mistakes
- Counting ninety days as three months, which drifts by a few days and can make you ineligible at the desk.
- Assuming platelets and whole blood share the same waiting period, when platelets can be donated far more often.
When to use it
- Use it to plan your next donation so you arrive after the mandatory rest period instead of being turned away.
- Use it to space platelet and whole blood donations safely when you donate both types regularly.
Worked example
If you last donated on 1 January 2025, the next whole blood date is 1 April 2025 and the next platelet date is 15 January 2025.
Common questions
Are these intervals the same everywhere?
No, national blood services set their own minimum gaps, though ninety days for whole blood and fourteen for platelets are common standards.
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