Calculating the concrete requirement or the required quantity of concrete in m³ is not at all difficult.
Then finding out how many packs or bags of dry concrete/dry concrete mix you have to buy for the calculated volume is a bit trickier. So if you want to mix concrete to fill a certain cubic meter and want to know how many bags of 25 kg concrete, 35 kg concrete or 40 kg concrete each can be bought, then you’ve come to the right place.
We show you how to calculate concrete quantities and how much dry mix you need.

*Nevertheless, when buying, pay attention to the information on the packaging and, if in doubt, ask a local specialist seller.*Cubic meters and the required amount of concrete: How many kg of ready-mixed concrete / dry mix are required for 1 m³ volume? Here you get answers and tips for calculation and determination.## Calculating Concrete Requirements: How many cubic meters do i need?

The first step in determining the concrete mixing requirements is, of course, the calculation of the volume to be filled. Classically, a cuboid with height, width and length is calculated here. If you want to make concrete furniture yourself, you may also have other shapes in mind, such as cylinders, cones or the like. There are also the right formulas for this. For example, for calculating a circle section to determine the base areas of individual parts. But let’s stick to the cuboid as the simplest body to be calculated. For the rectangular area you want to fill with concrete, first measure the height, width and length in meters. For example, let’s assume a room with a width of 2m and a length of 3.6m. The concrete is to be poured 10cm, i.e. 0.1m high. This results in the following calculation:2m x 3,6m x 0,1m = 0,72m³

This means that you need 0.72 cubic metres of concrete for the floor of the room. If you need help calculating or want to check your results, you can use the calculator on your PC, Mac, smartphone or tablet. Or you can visit an online calculator for cubic meters, like this one (click here).### Calculate Cylinder Volume

As can be seen above in the picture, concrete cylinders are well suited as decoration and demarcation in the garden. With a cylinder as a geometric shape, the volume calculation is a bit more complicated, but not impossible either. What you need is on the one hand the height of the concrete cylinder and on the other hand its base area. The height can easily be determined with a ruler or folding ruler. Calculate the base area as follows:A=π*r² (A = area; r = radius) / or alternatively: A=(π*d²)/4 (d = diameter)

Use a value for r or d in meters for the calculation. Also use a meter for the height of the cylinder. Then simply calculate V=A*h (V = volume; h = height) for the volume. A more detailed explanation and calculation examples for cuboids, cylinders and spheres can be found here (click).### How many kg on Ready-Mixed Concrete do i need for 1m³?

This is how 1m3 cube looks like. For the first calculation example, let’s assume 40 kg of ready-mixed concrete that you want to use for mixing concrete. Once you have finished your mould for pouring the concrete, measured everything accurately and calculated the volume, you assume a rough figure of 21 litres of concrete after mixing 40 kg of concrete mixture. Since 1m³ corresponds to a volume of 1,000l, you therefore calculate 1,000 / 21. 48 rounded bags of ready-mixed concrete of 40 kg each or a total of 1,920kg of ready-mixed concrete per cubic meter are required. However, you must also make sure that there are different types of concrete, such as fast concrete and similar types. Various instructions and regulations therefore also state that you need about 56 packs of dry concrete of 40kg each for 1m³, which results in about 17.86 litres of liquid concrete per pack.**look at the packaging when buying the dry concrete or talk to the seller in the trade / DIY store – he should be familiar with the quantity of concrete to be expected and the quantity of water to be added beforehand.***An important tip*:### How long does Concrete have to harden?

Despite its relatively simple components, concrete is a complex mixture of materials that only reaches a so-called standard strength or minimum compressive strength after about one month. Once you have successfully calculated the volume of the room to be filled and know how many kilograms of ready-mixed concrete you need for the cubic meter quantity determined, then the concrete is easy to mix and pour. Then wait at at least 12°C and average humidity for about 28 days. Then you can process the cast parts further or build on, seal, paint or otherwise process the cast concrete surface. Further facts and tips on the composition of concrete and the period during which concrete has to harden can be found in this article (click).*.*