Preservative Dose For Cosmetics Calculator

Work out preservative dose for cosmetics instantly with clear inputs, formula shown and shareable results.

About Preservative Dose For Cosmetics Calculator

Preservative dose is the supplier's recommended use level capped at the regulatory maximum for the ingredient. Any product containing water needs preservation; truly anhydrous products generally do not. The dose must be justified by challenge testing, not by the label recommendation alone.

Formula

Preservative dose

Preservative (g) = batch size x min(recommended use %, regulatory maximum %) / 100

Worked example

With the default values below, Preservative Dose For Cosmetics Calculator returns Preservative Required of 10.0000. Change any input above and every figure here is recalculated in your browser.

Inputs used

Batch Sizeminimum 0 g: 1,000 g
Recommended Use Levelaccepts 0–10 %: 1 %
Product Water Contentaccepts 0–100 %: 70 %
Regulatory Maximumaccepts 0–10 %: 1.2 %

Results

Preservative Required: 10.0000
Dose Applied: 1.0000%
Headroom To Regulatory Maximum: 0.2000%
Preservation Assessment: Water present - preservation essential

Step by step

1Values used
2Preservative dose
3Preservative Required= 10.0000
4Dose Applied= 1.0000
5Headroom To Regulatory Maximum= 0.2000
6Preservation Assessment= Water present - preservation essential

Assumptions and limits

The result is derived only from the 4 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 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Preservative use levels are legally capped and preservative efficacy must be demonstrated by challenge testing under cosmetic safety regulation.

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

Preservative use levels are legally capped and preservative efficacy must be demonstrated by challenge testing under cosmetic safety regulation.

Frequently Asked Questions

Is a preservative always needed?

Whenever water is present and the product will be exposed to contamination in use. Anhydrous oils, balms and waxes usually do not need one, but any water ingress changes that.

What is challenge testing?

Deliberately inoculating the product with specified organisms and monitoring their reduction over time. It is the only evidence that a preservative system actually works in that formula.