Rip Rap Calculator



Note: values cannot be equal to or less then 0




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Introduction to Rip Rap Calculator

Calculating a rock's diameter can be challenging and time consuming task. There are also chances of one doing any mistake while doing manual calculations. That is why we introduce the rip rap calculator to calculate the rock's diameter.

Data is required to calculate the riprap stone-like (velocity of water, gravity, and bash). With the help of the data, rip rap rock calculator can determine the size of the rocks.

Why use riprap weight calculator?

The online rip rap stone calculator provides you with the measurement of the rocks according to the water velocity, bash constant, and specific gravity. Riprap sizing calculator helps you to calculate 100 % accurate results without any errors.

The calculation of rip rap by hand is very difficult as there can be errors. The riprap coverage calculator executes the values according to the formula and provides the results within a minute.

How to use the rip rap volume valculator?

The use of the rip rap cost calculator is very simple. If you want to know how much rip rap do I need? There are a few simple steps to follow as below:

  • Open the riprap rock sizing calculator.
  • Input the values (velocity, gravity and bash constant).
  • Click on the calculate rip rap button.
  • The results will show after a minute.

To reuse the riprap size calculator, click on the calculate again button, which will load back the calculator page.

How to calculate a riprap rock's size?

It is easy to estimate the rip rap rocks. You can follow the formula and get the calculation by manual method.

Rip rap calculation formula

$$ D_{50} \;=\; \frac{(v)^2}{(2 \;×\; g \;×\; c^2 \;\;×(s-1))} $$


D50 is the Average diameter of 50% of the spherical rocks for the rip rap in meters.

V is the Average channel velocity in meters per second.

G is Acceleration due to gravity, either 9.806 m/s² or 32.17 ft. /s²

C is Isbash constant with values equal to 0.86 for highly turbulent flow of water or 1.20 for low turbulence water flow.

S is Specific gravity of the rock ranges from around 2.50 to 3.00.


There are few values: velocity 1ms, bash constant 1.2, and specific gravity 2.6. Calculate the rip rap in cm.


$$ D_{50} \;=\; \frac{(v)^2}{(2 \;×\; g \;×\; c^2 \;×\; (s \;-\;1))} $$ $$ D_{50} \;=\; \frac{(1 m/s)^2}{(2 \;×\; 9.802 m/s² \;×\; 1.2² \;×\; (2.6 \;-\; 1))} $$ $$ D_{50} \;=\; \frac{1\; m²/s²}{(19.612\; m/s² \;×\; 1.44 \;×\; 1.6)} $$ $$ D_{50} \;=\; \frac{1\; m²/s²}{(45.186048\; m/s² )} $$ $$ D_{50} \;=\; 0.02213 m $$ $$ D_{50} \;=\; 2.21 cm $$

Advantages of the online riprap calculator

There are some beneficial uses of the rip rap tool as below:

  • The rip rap volume calculator provides you with accurate output quickly.
  • Rip rap rock calculator saves your time and energy from difficult calculations.
  • It is a reliable converter you can trust on it to know how much rip rap do I need.
  • It saves your money from premium calculators to calculate rip rap.
  • Rip rap calculator is available at any time.
  • It is a very helpful tool for engineers to measure the size of rocks.

Other related tools

There are other related tools which you can find on this website. The online calculators are:


How does the rip rap tool execute the values?

The riprap sizing calculator has a built-in formula set by the developers; when you enter the values, it executes automatically and provides the results after calculation.

Is it a reliable tool for rip rap calculation?

The developers of the rip rap stone calculator tested it many times then it was available for people's use.

What is riprap?

The line of the rocks between water and land is called rip rap. It is used to control the water stream because the velocity of the water is very high in the rivers and oceans.

The high velocity of the water can destroy the layer of the land inside the water. That is why we use the different sizes of the rocks according to the flow of water.

How much rip rap do i need?

The amount of rip rap needed depends on the size and slope of the area to be protected, as well as the desired level of erosion control. A professional engineer should be consulted to determine the specific requirements for your project.

Alan Walker

Shaun Murphy

Last Updated March 28, 2022

A professional content writer who likes to write on science, technology and education.