How do you calculate dosing accuracy?

Subtract the target dose from the delivered dose to get the margin, then divide by the nominal reference dose. Delivering 125 g against a 100 g target with a 100 g reference gives a 25 g margin, or 25%.

What is an acceptable dosing accuracy tolerance?

It depends on the ingredient: major bulk additives may allow plus/minus 2-3%, while potent actives are often held to plus/minus 1% or tighter. A 25% margin like the example is far outside any normal window and points to a wrong setpoint or a scaling error.

Is dosing accuracy the same as precision?

No. Accuracy is how close the delivered dose is to target; precision is how repeatable successive doses are. A doser can be precise but inaccurate if it consistently overshoots by the same amount.

Why express dosing margin against a reference instead of the target?

Using a fixed nominal reference lets you compare margins across ingredients on a common basis and matches how recipe tolerances are often written against the nominal charge rather than the achieved value.

What does a positive dosing margin mean?

A positive margin means the delivered dose exceeded the target, an overdose. In the example the 25 g positive margin means 25% more material than specified was delivered, which for most actives would reject the batch.

How do I reduce dosing overshoot?

Tune the feeder's dribble or fine-feed cutoff, reduce in-flight material by lowering the fast-feed rate near target, and confirm scale settling time. Overshoot usually comes from material still in flight when the coarse feed stops.

Weighing, Dosing & Loss-in-Weight Feeding calculator

Dosing Accuracy Calculator

Dosing Accuracy quantifies how far a delivered dose deviates from its target mass, expressed as a percentage of a reference recipe amount. Formulators, batch operators, and quality engineers on pharmaceutical, food, and chemical dosing lines use it to prove each additive was metered within spec. Because a small percentage error on an active or minor ingredient can push a whole batch off-formula, this margin is a first-line acceptance check. It converts a raw gram difference into a normalized figure you can compare across ingredients of very different weights.

What this calculator does

Dosing Accuracy quantifies how far a delivered dose deviates from its target mass, expressed as a percentage of a reference recipe amount.
Use it when dosing accuracy in weighing, dosing and loss-in-weight feeding needs a clean margin number for a weighing, dosing and loss-in-weight feeding go / no-go review.
It computes the mass margin between the delivered dose and the target, then expresses that margin as a percentage of a nominal reference dose.

Formula used

Dosing Accuracy margin = available value - required value
Margin percent = margin ÷ reference value

Inputs explained

Delivered dose mass:
Target dose mass:
Nominal recipe dose:

How to use the result

Use it at batch qualification or during commissioning to verify a doser meters each ingredient within its allowed tolerance window.
A positive margin only tells you the direction and size of the average deviation, not its repeatability; a doser that alternates over and under can average near zero yet still fail.

Common questions

How do you calculate dosing accuracy? Subtract the target dose from the delivered dose to get the margin, then divide by the nominal reference dose. Delivering 125 g against a 100 g target with a 100 g reference gives a 25 g margin, or 25%.
What is an acceptable dosing accuracy tolerance? It depends on the ingredient: major bulk additives may allow plus/minus 2-3%, while potent actives are often held to plus/minus 1% or tighter. A 25% margin like the example is far outside any normal window and points to a wrong setpoint or a scaling error.
Is dosing accuracy the same as precision? No. Accuracy is how close the delivered dose is to target; precision is how repeatable successive doses are. A doser can be precise but inaccurate if it consistently overshoots by the same amount.
Why express dosing margin against a reference instead of the target? Using a fixed nominal reference lets you compare margins across ingredients on a common basis and matches how recipe tolerances are often written against the nominal charge rather than the achieved value.
What does a positive dosing margin mean? A positive margin means the delivered dose exceeded the target, an overdose. In the example the 25 g positive margin means 25% more material than specified was delivered, which for most actives would reject the batch.

Last reviewed 2026-05-12.