Health & fitness · Medication math
Liquid medicine dose converter.
Enter the concentration from the label (mg per mL amount) and a dose. Get mL, teaspoons and a check against the label maximum you type in.
Not medical advice
This tool only does arithmetic on numbers you type in from your own prescription or package label. It does not recommend any drug, dose or schedule. Follow your prescriber, pharmacist and the label, and ask them before changing how you take any medicine.
Inputs
Converted dose
Enter the numbers above.
How the conversion works
The label gives a concentration such as 160 mg per 5 mL. That is 160 / 5 = 32 mg in each mL. A dose in mg divided by mg per mL is the volume in mL. A teaspoon is 5 mL: the US FDA Drug Facts rule writes the dose unit as a "5 mL teaspoonful", so mL divided by 5 is teaspoons.
Worked example (arithmetic only, not a dose suggestion). At 160 mg per 5 mL (32 mg per mL), a dose of 240 mg is 240 / 32 = 7.5 mL, which is 1.5 teaspoons. If the label maximum single dose you typed is 320 mg, that is 10 mL, so 240 mg is under it.
Measure liquid medicine with the syringe, cup or spoon that comes with it, as the NHS advises. Check the strength on the bottle every time, because the same medicine can be sold in different concentrations.
Frequently asked questions
How do I convert mg to mL for liquid medicine?
Divide the dose in mg by the number of mg in each mL. A label of 160 mg per 5 mL is 32 mg per mL, so 240 mg is 7.5 mL.
How many mL is a teaspoon?
For medicine labels a teaspoon is 5 mL. The US FDA OTC Drug Facts rule uses a "5 mL teaspoonful" as the dosage unit.
Should I use a kitchen spoon to measure?
Use the syringe, cup or spoon supplied with the medicine, as the NHS advises, rather than a spoon from the kitchen.
Why does the tool ask for the label maximum?
It is only a cross-check. You type the maximum single dose printed on your label and the tool tells you if the dose you entered is above it. It does not know any maximum itself.
Sources
Checked
- 21 CFR 201.66, "Format and content requirements for over-the-counter (OTC) drug product labeling", eCFR, opened 8 October 2026. Drug Facts active-ingredient line uses "5 mL teaspoonful" as the dosage unit
- NHS, "Ibuprofen for children: medicine for pain and high temperature", opened 8 October 2026. Always use the syringe or spoon that comes with the medicine to measure the amount
The tool does not use any drug-specific dose. Runs entirely in your browser. Nothing you type is sent or stored.
Scope
The label concentration, the dose and the maximum are all numbers you enter; none is supplied by this tool. This is a calculation aid, not medical or pharmacy advice, and it does not know your medicine, your health or your prescription. Your label, prescriber and pharmacist decide.