Vitamin D2 Unit Converter

Vitamin D2 (ergocalciferol) is one of two main forms of vitamin D measured in blood tests. It comes from plant sources, UV-exposed fungi, and fortified foods.

Your body converts vitamin D2 into its active form (1,25-dihydroxyvitamin D) through the liver and kidneys. This active form helps regulate calcium absorption and supports bone health.

Most labs report vitamin D2 and D3 separately or as a combined total 25(OH)D value. Vitamin D2 is often undetectable unless you take D2 supplements or consume fortified foods. Both forms work similarly in the body, though D3 tends to raise and maintain blood levels more effectively.

Vitamin D2 is not produced by the human body. It comes from plant and fungal sources, including UV-exposed mushrooms, fortified plant milks, cereals, orange juice, and prescription or over-the-counter ergocalciferol supplements.