Testing & Quality Control

Pilling Propensity Index Calculator

A pill count means nothing without the cycles and the area it was counted over.

Test Martindale run
no.
no.
cm²
Rating Visual assessment
grade
grade

Pilling Index

— pills/1000 cycles

Pills formed per thousand Martindale cycles

Surface Assessment

Pill Density
— /cm2
Pills per Square Metre
— no.
Normalised Propensity
— /cm2 per 1000
Shortfall Against Rating
— grade

Visual rating remains the contractual result; these indices exist to compare fabrics tested to different cycle counts. Always report the cycle count alongside the grade.

Pilling Propensity Index Calculator — free, with the formula and a worked example, at Textile School.