Dosage Form Lab
Master Formula Calculator
Enter a master formula and the quantity you want to prepare — every ingredient is scaled for you, in its own unit.
Formulation
The master batch the formula is written for, and how much you want to make.
The quantity the master formula makes.
The quantity you want to prepare.
Master formula ingredients
Enter each ingredient exactly as it appears in the master formula.
Scaled formula
Enter the master formula and the quantity to prepare, then press Calculate.
References
- Stockton SJ. Stoklosa and Ansel's Pharmaceutical Calculations. 16th ed. Philadelphia: Wolters Kluwer; 2021.
Common questions
The number every ingredient is multiplied by to change the batch size. It is the desired quantity divided by the master formula quantity: to make 100 mL from a 1000 mL formula, 100 ÷ 1000 = 0.1, so each quantity becomes one tenth.
Yes. If the desired quantity is larger than the master batch the factor is greater than 1 — making 2 L from a 500 mL formula gives 2000 ÷ 500 = 4.
A percentage is a concentration, not an amount. A preparation containing 10% glycerin contains 10% glycerin whether you make 1000 mL or 100 mL, so the percentage is carried over unchanged.
Choose q.s. as the unit. It has no quantity of its own — in the scaled formula it becomes 'q.s. to' the required quantity, meaning add enough of that ingredient to make up the final volume or weight.
Prepared by the PharmaWallah student team. Verify results with your textbook or instructor. Report an error · Editorial policy