Back-calculate tablet weight and a fully custom excipient breakdown from API dose and %w/w.
Tablet weight isn't usually the starting point of a formulation — the API dose per tablet is fixed by the label claim, and the percentage that API is meant to represent in the final tablet (its %w/w) is decided during formulation development. This calculator works backwards from those two numbers to arrive at the theoretical tablet weight, which is the number formulation and QC teams actually work with day to day.
From there, each excipient's percentage of the tablet is converted into an actual milligram weight, so you can see exactly how much diluent, binder, disintegrant, lubricant, or glidant a single tablet is expected to contain. The balance check flags whether your excipients, together with the API, add up to 100% of the tablet weight — a quick way to catch a formulation error before it reaches a batch record.
You can rename, add, or remove excipient rows freely, so the same layout works whether you're documenting a simple five-excipient formula or a more complex one with multiple diluents or coating-related components.
Tablet weight sits at the center of two very different concerns: getting the formulation math right during development, and passing a weight variation test during routine quality control. A reliable starting figure here has real downstream value for both formulation scientists building a new product and QC teams monitoring a running batch.
Divide the API dose per tablet by the percentage the API represents in the formula (its %w/w).
It's the percentage of a tablet's total weight that a given ingredient — the API or an excipient — makes up.