insulin syringe calculator
Calculator / Reference

Reconstitution concentration calculator

Check the arithmetic between total vial strength, confirmed final solution volume and U-100 syringe markings.

01

Enter your label values

mL

Use the confirmed final volume for the whole vial, not a mixing recommendation.

Enter the amount already specified by your prescriber. This tool does not choose it.

02 Match your syringe

All three use the U-100 scale: 100 units per mL.

Only for U-100 syringe markings. Check the scale printed on the barrel.

YOUR CALCULATION On your device

A little clarity, in units.

Enter your values and select the markings on your syringe. Your result and the full arithmetic will appear here.

Syringe viewU-100
← Needle endSelect your syringe
Illustration only. Read the plunger edge nearest the needle. Check the markings on your actual syringe.

Measurement, not medical advice. Confirm your prescribed amount and how to measure it with your prescriber or pharmacist. This tool does not calculate an insulin dose or convert biological IU to mg.

No account. No tracking. Just the calculation.

Saved calculations 0 on this device

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THE REFERENCE

This is a concentration calculation

Reconstitution instructions are specific to a product. This page does not tell you which liquid to use, how much to add, how to prepare an injection, or how long to store it. Use the instructions supplied by the manufacturer, pharmacist or prescriber.

Final volume is the value the maths needs

Concentration equals total mass divided by final solution volume. The quantity of liquid added is not automatically an independently confirmed final volume. If you have only a mixing instruction and are unsure of the resulting concentration, ask the dispensing pharmacist before calculating.

What changes when the volume changes

For the same total vial mass and entered amount, doubling the final solution volume halves the concentration and doubles the volume needed. On a U-100 syringe, that also doubles the calculated markings. This describes a relationship, not a suggestion to alter a preparation.

Use the total mass field correctly

If the label gives only a concentration such as mg/mL, do not enter that number as the total vial strength. You also need the confirmed total volume to derive the total mass. Check that both values refer to the same preparation and that mg and mcg have not been mixed.