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Peptide mg / mcg / IU Converter

Convert between milligrams, micrograms, nanograms and international units in one place.

For research & education only. This tool performs unit conversion on the values you enter. It is not medical advice and does not recommend doses. Research use only.

Peptide amounts are quoted in milligrams (mg), micrograms (mcg) and sometimes international units (IU). This converter moves between metric mass units instantly, and — when you supply a conversion factor — estimates IU.

Metric conversions are fixed

UnitEquals
1 mg1,000 mcg
1 mcg1,000 ng
1 mg1,000,000 ng

IU is not a mass unit

International units measure biological activity, not weight, so there is no universal mg ↔ IU conversion. Each substance has its own factor, usually printed on the vial or certificate of analysis. Enter that factor (mg per IU) and the tool will estimate IU alongside the mass conversion.

Frequently Asked Questions

How many mcg in a mg?
1 milligram equals 1,000 micrograms. So 0.25 mg is 250 mcg, and 2.5 mg is 2,500 mcg.
Can you convert mg to IU?
Only with a substance-specific factor. IU measures biological activity, not mass, so the mg-to-IU ratio differs per compound. Use the factor printed on your vial or certificate of analysis.

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