Enter the Reynolds number into the calculator to determine the Darcy Friction Factor. This calculator can also evaluate any of the variables given the others are known.

## Darcy Friction Factor Formula

The following formula is used to calculate the Darcy Friction Factor.

f = 0.0791 / (Re)^{0.25}

Variables:

- f is the Darcy Friction Factor (dimensionless)
- Re is the Reynolds number (dimensionless)

To calculate the Darcy Friction Factor, divide 0.0791 by the Reynolds number raised to the power of 0.25.

## What is a Darcy Friction Factor?

The Darcy Friction Factor, also known as the Darcy-Weisbach friction factor, is a dimensionless quantity used in fluid dynamics to represent the resistance to flow in a pipe. It is a key parameter in the Darcy-Weisbach equation, which relates the head loss, or pressure loss, due to friction along a given length of pipe to the average velocity of the fluid flow. The factor depends on the roughness of the pipe’s interior surface and the Reynolds number, a measure of the flow’s turbulence.

## How to Calculate Darcy Friction Factor?

The following steps outline how to calculate the Darcy Friction Factor.

- First, determine the Reynolds number (Re) value.
- Next, substitute the Reynolds number value into the formula: f = 0.0791 / (Re)^0.25.
- Finally, calculate the Darcy Friction Factor (f).
- After inserting the Reynolds number value and calculating the result, check your answer with the calculator above.

**Example Problem:**

Use the following variables as an example problem to test your knowledge.

Reynolds number (Re) = 5000