Vitamin D Calculator
vitamin d calculator. Get instant, accurate results. Enter values for instant results with step-by-step formulas.
Reviewed by Rahul Singh, Health & Wellness Specialist
Formula
Approximate Total Loading Dose (IU) = (Target - Current) x Body Weight (kg) x 10
This formula estimates the total supplemental (loading) dose of Vitamin D needed to raise serum levels to the target, not a daily dose. Roughly 10 IU per kg of body weight per ng/mL of deficit is required over a correction period. Divide this total by the number of days in your loading period to determine a daily dose, always under medical supervision. Optimal range: 40-60 ng/mL. Deficient: <20 ng/mL. Insufficient: 20-30 ng/mL. Toxic: >100 ng/mL. Safe daily upper limit without medical supervision: 4,000 IU. Consult your doctor.
Worked Examples
Example 1: Level 20 to target 50
Problem:Current 20 ng/mL, target 50 ng/mL, 70 kg
Solution:Deficit: 30 ng/mL. Total Loading Dose = 30 x 70 x 10 = 21,000 IU. This is the estimated total supplemental dose, not a daily amount. Example: split over 5-10 days as ~2,000-4,000 IU/day under medical supervision. Maintenance ~2,000 IU/day thereafter.
Result:~21,000 IU total loading dose (consult doctor — do not take as a single daily dose)
Reviewed by Rahul Singh, Health & Wellness Specialist · Editorial policy