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Resistivity Index - Archie's Law Calculator

RI=RtRoRI=\frac{R_t}{R_o}

Enter the required inputs, confirm the units, and run the calculator to solve RI. Review the formula source and assumptions before using the result in engineering work.

Tabular solver

Inputs

Defaults provide a quick field-unit example for the equation.

2 variables

Calculation runs locally with the shared TypeScript engine.

Formula reference

Resistivity Index - Archie's Law calculates resistivity index for resistivity logs workflows in petrophysics.

View formula, units, and source

Assumptions

  • Input values are representative for the well, reservoir, fluid, or equipment case being evaluated.
  • The declared units match the field-unit constants used in the formula.
  • The cited formula applies to the selected petroleum engineering workflow.

Common mistakes

  • Mixing unit systems without converting the inputs.
  • Using default example values as field recommendations.
  • Applying the formula outside the source assumptions.