Lubricant Viscosity Calculator

A Set of Calculation Tools Based on Standard ASTM Methods

1Viscosity at Any Temperature
2Two-Oil Blend Ratio
3Blend Viscosity of Two Oils
4Viscosity from VI
5Viscosity at 40°C from VI
6Viscosity at 100°C from VI

Calculate Viscosity at Any Temperature (ASTM D341)

Given the viscosity at two known temperatures, the viscosity at any desired third temperature is calculated.

Result
Enter the values

Calculate the Blend Ratio of Two Oils to Reach a Target Viscosity

Given the viscosity of two base oils and a target viscosity, the weight/volume percentage of each oil in the blend is calculated.

Result
Enter the values

Calculate the Blend Viscosity of Two Known Oils

Given the viscosity of two oils and the percentage of each in the blend, the final blend viscosity is calculated.

Result
Enter the values

Calculate Viscosity Index (VI)

Given the viscosity at 40°C (U) and the viscosity at 100°C (Y), the viscosity index is calculated according to ASTM D2270 (quadratic equation method).

Result
Enter the values

Calculate Viscosity at 40°C from VI

Given the viscosity index (VI) and the viscosity at 100°C (Y), the viscosity at 40°C (U) is calculated according to ASTM D2270.

Result
Enter the values

Calculate Viscosity at 100°C from VI

Given the viscosity index (VI) and the viscosity at 40°C (U), the viscosity at 100°C (Y) is calculated according to ASTM D2270.

Result
Enter the values