Units on a U-100 syringe
How many units is 100 mcg?
It depends on the concentration. With a 5 mg vial and 2 mL of water, 100 mcg is 4 units (0.04 mL). With a 10 mg vial and 2 mL, it’s 2 units.
Find your vial and water below, or enter your own numbers in the calculator.
100 mcg in units, by vial and water
| Vial | 1 mL water | 2 mL water | 3 mL water |
|---|---|---|---|
| 2 mg | 5units | 10units | 15units |
| 5 mg | 2units | 4units | 6units |
| 10 mg | 1units | 2units | 3units |
| 15 mg | 0.7hard to read | 1.3units | 2units |
| 20 mg | 0.5hard to read | 1units | 1.5units |
| 30 mg | 0.3hard to read | 0.7hard to read | 1units |
100-unit (1 mL) insulin syringe. “Won’t fit” = over 100 units; “hard to read” = under 1 unit.
Your numbers
On a 100-unit (1 mL) insulin syringe
Draw to 4 units
= 0.04 mL
How it’s calculated
Concentration
5 mg ÷ 2 mL = 2.5 mg/mL
One unit
2.5 mg/mL × 10 = 25 mcg per unit
100 mcg
100 mcg ÷ 25 = 4 units
Stop redoing this math.
Peptide Vault saves the calculation with your vial, logs every dose, and reminds you on schedule. iPhone, on-device.
FAQ
How many units is 100 mcg on an insulin syringe?
It depends on how the vial was mixed. With a 5 mg vial and 2 mL of water (2.5 mg/mL, 25 mcg per unit), 100 mcg is 4 units. With a 10 mg vial and 2 mL it is 2 units. Use the table or the calculator for your vial.
How many mg is 100 mcg?
100 mcg is 0.1 mg (1,000 mcg = 1 mg).
How many mL is 100 mcg?
Volume depends on concentration too. At 2.5 mg/mL (5 mg in 2 mL) 100 mcg is 0.04 mL; at 5 mg/mL (5 mg in 1 mL) it is 0.02 mL.
Why does more water mean more units?
The vial holds the same total either way. More water spreads it thinner, so each unit carries less and you need more units for the same amount.
Is this a recommendation?
No. 100 mcg is used here as an example amount for arithmetic. Peptide Vault does not recommend amounts; follow your prescriber or pharmacist.