How We Test

We are publishing the method before the results, so you can judge the method on its own terms rather than on whether you like the answer it produced.

Nothing on this site has been tested yet. The directory came first because it took months of price data to build. Testing starts once the protocol below is set up, and until then every product page says plainly that we have not run it.

Every product in a comparison meets the same soil on the same substrate. For pet formulas that means cut-pile carpet cut into identical squares from one roll, soiled with the same volume of the same fluid, aged the same number of hours before treatment.

Each product gets the dwell time its own label specifies. Where a label gives a range we use the midpoint. Where a label says nothing we use fifteen minutes and note it.

We photograph each square under normal light and under a 365nm blacklight, before treatment, immediately after, and at twenty-four hours. The blacklight matters because it shows residue that looks clean to the eye.