Automatically calculate your next eligible blood donation date based on your previous donation type and date to help you plan your donation schedule.
Enter your last donation information to see the results.

Child Height Predictor Calculator
Predict a child's potential adult height range based on parents' heights and gender, providing parents with a reliable growth trend reference.

Body Fat Calculator
Calculate your body fat percentage using BMI and waist circumference formulas. Get instant body composition insights for fitness and health management.

Creatinine Clearance Calculator
Enter your age, weight, and serum creatinine to quickly assess your kidney function.

BMR Calculator (Basal Metabolic Rate)
Calculate the minimum daily calories your body needs at rest based on gender, height, weight, and age. Get a scientific reference for your diet and fitness plans.

Fetal Weight Calculator
Estimate fetal weight using ultrasound measurements (BPD, AC, FL) with multiple standard obstetric formulas.
Blood donors often forget their last donation date and are unsure when they can donate again. By taking your selected donation type and the exact date of your last donation, this tool automatically calculates the earliest eligible date for your next donation based on national interval standards (e.g., 180 days for whole blood, 14 days for platelets). The donation interval is the minimum wait time required between two donations to ensure the donor's physical recovery and the safety of the blood supply.
What is the minimum interval for platelet donation?
14 days. According to Chinese blood center operating procedures, the minimum interval for platelet donation is 14 days.
Does the calculated result guarantee I can donate?
The result serves only as a time interval reference. Actual donation eligibility requires a health assessment by the blood center. Donors must meet health indicators such as weight and hemoglobin levels, and have no risk of infectious diseases.
Please ensure the entered date is accurate. The calculated results should be used in conjunction with your personal health status. Blood centers in different regions may have additional requirements. Frequent platelet donors should be aware of the annual limit (≤24 times/year).
We recommend regular donors keep a record of each donation type and date. For example, if you donate platelets on January 1, 2024, the tool will calculate your next eligible donation date as January 15, 2024. However, you must still pass a hemoglobin test before the actual donation (≥120g/L for men, ≥115g/L for women). If the test is not met, the donation must be postponed.