When you need to find the amount of rebar needed for a project, this calculator will do all the hard work for you. In one easy step, you can figure out how much rebar is required and what type of rebar to use. The calculator will also give you an estimate on how much material your project will require as well as any additional supplies that are needed.

What is rebar?

Rebar is a steel bar used to reinforce concrete. It’s a common construction material, and you might even have some in your home! Rebar can be found in concrete slabs, walls and columns. If you have ever worked on a construction site or seen a building under construction, you’ve probably noticed rebar sticking out of the side of buildings—it’s usually gray or silver with ridges on it.

The purpose of rebar is to strengthen concrete by connecting it together while also transferring loads from one section to another. Concrete expands when wet and shrinks when dry—even though we don’t notice its movement much because it’s slow—and without rebar to connect the pieces together they would crack apart over time due to expansion/contraction.

What are rebars used for?

Rebar is used to reinforce concrete. It prevents cracks from forming due to the movement of the concrete and also gives it strength. The main reason why rebar is used in reinforced concrete is because it’s a strong material, but it can be expensive depending on where you live. It’s also used in many other things, including:

  • Concrete slabs
  • Concrete walls
  • Concrete columns
  • Concrete beams

When were rebars invented?

Rebars are the steel bars that reinforce concrete and give it strength. They were first used in construction in the early 20th century and replaced wooden forms as well as concrete, thanks to their ability to withstand constant pounding without buckling. The rebar is also critical for ensuring that concrete has enough tensile strength and durability.


Rebar was first invented in the early 1900s and used in construction by 1940. It’s made of steel, and is commonly used to reinforce concrete. Rebar makes concrete strong; without it, buildings would not be able to withstand earthquakes or high winds as well as they do now.

Rebar can also be used for other purposes such as reinforcing existing concrete structures and creating new ones where needed. It’s also sometimes used on its own to create sculptures or other pieces of artwork that require a lot of strength (like fences). Finally, rebar is used in barbecue grills because it conducts heat very well!

How to use the rebar calculator

If this calculator seems confusing, let me try to fix that. With this calculator, you’re trying to calculate the dimensions of your rebar grid (length and width). In order to calculate this, you need to input the length and width of your slab. the calculator will give you the default spacing values (for rebar – rebar it’s 40cm, and for edge – grid it’s 8cm). Once you input these values, you will have your grid length dimensions, it’s that easy.

As well as that, the calculator will also tell you the total length of the rebars, the number of rebar pieces you need, and the total cost.


How much rebar do I need?

If you’re wondering how much rebar you need, you have come to the right place. This calculator will tell you how much rebar you need, based on the dimensions of your slab.

How far apart should rebar be spaced?

12 inches is the recommended distance.

How thick should rebar be?

It depends on its use. Standard driveway rebar is about 4-5 inches thick.