The viscosity index (VI) is an arbitrary, unit-less measure of a fluid's change in viscosity relative to temperature change. It is mostly used to characterize the viscosity-temperature behavior of …

Calculator for viscosity index (VI) according to ASTM D2270 and ISO 2909.

The change in an oil’s viscosity due to a temperature change is called the viscosity index (VI). Understanding VI is important to discern whether the lubricant in question meets the asset’s …

The viscosity index, commonly designated VI, is an arbitrary numbering scale that indicates the changes in oil viscosity with changes in temperature. Viscosity index can be classified as follows: low VI - …

The Viscosity Index (VI) is a dimensionless parameter used to describe the variation of kinematic viscosity of an oil with temperature changes. It is an important property that determines the suitability …

Sep 15, 2025 · Viscosity is an oil’s resistance to flow, but what really matters is how that viscosity changes with temperature. This is measured by the Viscosity Index (VI). Oils with a high VI stay …

Viscosity index means that it measures the change in viscosity with temperature – a high viscosity index indicates a small viscosity change of a petroleum product with changes in temperature.

Jun 19, 2025 · The Viscosity Index (VI) is a critical metric used to gauge how much a fluid's viscosity changes as temperature changes. A fluid with a high VI indicates a minimal change in viscosity …

The Viscosity Index is a measure for how much the oil viscosity changes as a function of temperature. Contrary to what you might expect, a higher Viscosity Index means a smaller change in viscosity.

Learn the step-by-step process to determine the Viscosity Index (VI) of a lubricant using ASTM D2270 standards.