Skip to the arithmetic
Dosing ArithmeticVial yield and repeat-interval arithmetic, on figures you supply.

The worksheets

Six, each taking different figures and answering a different question. Two of them are this site's own; four are the conversions the two depend on.

Educational arithmetic only. Not medical advice and not a dosing protocol.

  • Whole draws in a vialA vial strength and an amount per draw: the count, the leftover, and the span at an interval you give.
  • Repeat-interval arithmeticA half-life and an interval, both yours: the retained fraction and the multiple the peaks approach.
  • The decay curveOne half-life plotted, with the exact fractions at whole multiples of it.
  • Amount to volumeThe measurement step: one of those draws, at a strength you know, on a barrel you pick.
  • Vial to strengthA mass and a diluent volume into a strength, labelled as the ceiling it is.
  • Barrel unitsA volume into units on any of the five common calibrations, in either direction.

Two of these are why this site exists

Vial yield and repeat-interval arithmetic. Neither is about measuring a draw; both are about what surrounds a repeated amount - how many a vial holds, and what a decay constant implies when one follows another. Those are the questions the name of this domain points at, and they are the two that are answered here in full.

The other four are conversions: an amount into a volume, a vial into a strength, a volume into a barrel reading. They are here because the first two are incomplete without them. A draw count that cannot be measured is useless, and a strength that was derived without its bound is misleading.

All six share one engine

Every figure on this site comes out of the same calculation engine. The exact arithmetic holds quantities as fractions of whole numbers and rounds once, at the point of display. The kinetic arithmetic cannot be exact, because the exponent is fractional, so it is computed in floating point and every figure it produces is labelled approximate.

Which figures are which is set out on exact and approximate, and the static tables under by half-life and by interval are generated by the same functions the worksheets call.