Convert mg, mcg, g, mL and CFU exactly, and convert IU for vitamins A, D and E using nutrient- and form-specific factors from FDA guidance, plus DFE and NE helpers.

This tool provides automated labeling assistance and general information. Requirements vary by product, formulation, market and regulatory status. Verify your final label against current applicable regulations and obtain professional regulatory advice where appropriate before commercial use.

Exact metric conversions

Mass (g, mg, mcg), volume (L, mL) and energy (kcal, kJ) conversions are exact decimal calculations with no floating-point drift. For example, 2,500 mcg = 2.5 mg and 1 kcal = 4.184 kJ. CFU counts convert between CFU, million CFU and billion CFU (5 billion CFU = 5,000 million CFU = 5,000,000,000 CFU).

IU conversions are nutrient-specific

An International Unit is not a fixed weight. It depends on the nutrient and its form, so the converter only converts IU for vitamins A, D and E, using the factors in FDA’s guidance Converting Units of Measure for Folate, Niacin, and Vitamins A, D, and E on the Nutrition and Supplement Facts Labels (August 2019):

Vitamin D: 1 IU = 0.025 mcg (40 IU = 1 mcg)
Vitamin A as retinol: 1 IU = 0.3 mcg RAE. Supplemental beta-carotene: 1 IU = 0.3 mcg RAE. Dietary beta-carotene: 1 IU = 0.05 mcg RAE. Alpha-carotene: 1 IU = 0.025 mcg RAE
Vitamin E, natural (d-alpha-tocopherol): 1 IU = 0.67 mg. Synthetic (dl-alpha-tocopherol): 1 IU = 0.45 mg

The converter does not offer a generic “IU to mg” conversion for other substances, because no single factor exists.

DFE and NE helpers

mcg DFE = mcg food folate + 1.7 × mcg folic acid. mg NE = mg niacin + mg tryptophan ÷ 60. US labels declare folate in mcg DFE and niacin in mg NE, so use these before calculating % Daily Value.