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Enter any amount in mcg, mg, mL, or U-100 insulin units, plus your solution’s concentration, to convert it into all the other units at once — handy for reading a dose off a syringe or checking a label. To turn a target dose into the exact units to draw, use the mg-to-units converter. Reference math, not medical advice.
1000 mcg = 1 mg. On a U-100 syringe, 100 units = 1 mL (1 unit = 0.01 mL). Converting between mass (mcg/mg) and volume (mL/units) needs the solution concentration — set it above. To turn a target dose into the exact units to draw, use the mg-to-units converter. Arithmetic only, not medical advice.
Frequently asked questions
How do you convert mcg to mg (and back)?
There are 1000 micrograms (mcg) in 1 milligram (mg), so divide mcg by 1000 to get mg, or multiply mg by 1000 to get mcg. This is a pure mass conversion and does not depend on concentration.
How do milligrams relate to milliliters?
Through concentration. Milliliters equal milligrams divided by the concentration in mg per mL, and milligrams equal milliliters times the concentration. That is why this converter asks for the concentration of your reconstituted solution.
What is a U-100 syringe unit in milliliters?
On a U-100 insulin syringe there are 100 units in 1 milliliter, so one unit is 0.01 mL. The unit marks are volume markings; multiply milliliters by 100 to get units, or divide units by 100 to get milliliters.
How is this different from the mg-to-units converter?
This tool converts a single amount between mcg, mg, mL, and units for reference. The mg-to-units converter is built around turning a target dose into the exact units to draw on the syringe. Use whichever matches your task; they share the same underlying math.
Does this handle IU (international units)?
No. International units (IU) are defined per substance by biological activity and do not convert to mass or volume with a single universal factor, so they are intentionally left out. The units here are U-100 insulin-syringe volume marks, not IU.