This tool does not recommend doses. Use only the dose your veterinarian prescribed.How we make money
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Updated 6 Nov 2026

Preparation calculator

Your vet prescribed a dose? Work out the concentration, how far to fill the syringe and how many doses are in the vial. It never suggests a dose.

This tool does not recommend doses. Use only the dose your veterinarian prescribed. Not sure? Ask a vet before you mix anything.
Per dose. This tool never suggests a dose.

Fill in the dose your vet prescribed, the vial content and the water to see the result.

Double-check every number with your vet before you give anything. Units assume a U-100 syringe, where 1 unit = 0.01 ml.

How the numbers are worked out

  1. Concentration is the vial content in mg, divided by the water added in ml.
  2. Volume to draw up is the prescribed dose, divided by the concentration.
  3. On a U-100 syringe, units are the volume in ml, multiplied by 100.
  4. Doses per vial is the vial content, divided by the prescribed dose.

Questions about the calculator

Does this calculator recommend a dose?

No. It has no default dose, no presets and no per-weight maths. It only converts the dose your vet prescribed into syringe units.

What is a U-100 syringe?

An insulin syringe marked in units, where 100 units equal 1 ml. So 1 unit is 0.01 ml.

What if I mix up mcg and mg?

1 mg is 1,000 mcg, so a mix-up changes the amount a thousandfold. Check the unit with your vet before you draw anything up.

No prescribed dose? Ask a vet

A licensed vet by video or chat can tell you whether anything makes sense for your animal.

Ask a vet first