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VialBook
Vial math

Your numbers, shown step by step.

Type the numbers from your own vial and prescription. The math is shown in full so you can check it.

This only reflects the numbers you type. It does not suggest a dose and is not medical advice. The values shown are examples: replace them with your own, and check the result with your doctor or pharmacist.
Your vial
ResultLive
Concentration
5.0000
mg/mL
Draw volume
0.2000
mL
On U-100
20
units
10 mg ÷ 2 mL = 5.0000 mg/mL · 1 mg ÷ 5.0000 mg/mL = 0.2000 mL · ×100 = 20 units
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Units shown for a U-100 insulin syringe (1 mL = 100 units). mL and concentration are shown to 4 decimals, units to 1 decimal · the full math is above.

Questions
What does this calculator do?

It does arithmetic on the numbers you type: the amount in the vial divided by the liquid gives a concentration, and your dose divided by the concentration gives the volume to draw. It then converts that volume to units on a U-100 insulin syringe.

Does it tell me what dose to take?

No. It never suggests a dose. Your doctor or pharmacist tells you your dose. Check your numbers with them.

Is anything saved?

No. The math runs in your browser. Nothing you type is sent or stored.

What is a U-100 syringe?

On a U-100 insulin syringe, 1 mL equals 100 units. If your syringe is different, the unit conversion here will not apply.

Log it in 2 taps.

Free on iPhone. Two taps to your first dose.