Ointment Base Quantity Calculator

Work out ointment base quantity instantly with clear inputs, formula shown and shareable results.

About Ointment Base Quantity Calculator

Subtracts the active ingredient and any other components from the total mass to give the quantity of ointment base needed.

Formula

Base quantity

Active mass = total mass x strength; base = total mass - active mass - other ingredients

Worked example

With the default values below, Ointment Base Quantity Calculator returns Ointment base required of 54.000. Change any input above and every figure here is recalculated in your browser.

Inputs used

Total ointment to prepareaccepts 1–5,000 g: 60 g
Active ingredient strengthaccepts 0.01–50: 5
Other ingredientsaccepts 0–500 g: 3 g

Results

Ointment base required: 54.000 g
Active ingredient mass: 3.000 g
Base share of the preparation: 90.00%
Components summed: 60.000 g

Step by step

1Values used
2Base quantity
3Ointment base required= 54.000 g
4Active ingredient mass= 3.000 g
5Base share of the preparation= 90.00
6Components summed= 60.000 g

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 3 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Educational estimate only. Not a substitute for professional clinical judgement, and must not be used to make treatment or dosing decisions.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Educational estimate only. Not a substitute for professional clinical judgement, and must not be used to make treatment or dosing decisions.

Frequently Asked Questions

Why does the base quantity matter?

Adding the full base mass on top of the active would raise the total and dilute the intended strength.

Which base should be chosen?

It depends on the site and the drug: paraffin bases occlude, emulsifying bases wash off and cream bases suit weeping lesions.