Ready Mix concrete calcualtor


10/7/20233 min read

Concrete is the backbone of countless construction projects, from sidewalks and patios to foundations and beyond. Whether you're a DIY enthusiast or a professional builder, knowing how much concrete to order is crucial for a successful project. In this guide, we will take you through the process of calculating your concrete requirements with precision.

Why Calculating Concrete Matters:

Before we dive into the calculations, let's understand why it's essential to get your concrete quantities right:

  1. Cost Efficiency: Ordering the right amount of concrete helps you avoid unnecessary expenses. Overordering means wasted material, while underordering can lead to project delays and additional costs.

  2. Time Savings: Precise calculations ensure you have enough concrete on-site to complete your project without interruptions. This saves valuable time and minimizes inconvenience.

  3. Environmental Impact: Minimizing waste by ordering the correct amount of concrete is environmentally responsible. It reduces the carbon footprint associated with the production and disposal of excess material.

The Concrete Calculation Process:

To determine how much concrete you need, follow these straightforward steps:

1. Measure the Dimensions: Begin by measuring the length, width, and thickness of the area where you'll be pouring the concrete. Make sure to use consistent units of measurement (e.g., feet or meters).

2. Convert Thickness to Feet: If your thickness measurement is in inches, convert it to feet by dividing by 12. This ensures that all measurements are in the same unit.

3. Calculate the Volume: Multiply the length, width, and thickness (in feet) to find the volume in cubic feet. This represents the total space that the concrete will occupy.

4. Convert to Cubic Yards: Since concrete is typically sold in cubic yards, divide the cubic feet by 27 (1 cubic yard equals 27 cubic feet) to get the volume in cubic yards.

5. Account for Wastage: It's prudent to include a margin for wastage during mixing and pouring. Adding an extra 10% to 15% to your calculated volume ensures you have some leeway for unforeseen issues.

6. Choose the Right Bag Size: Depending on your project's volume, select the appropriate bag size of premixed concrete. Common sizes include 80 lb, 60 lb, 50 lb, 40 lb, and 90 lb bags.

7. Calculate the Number of Bags: Divide your adjusted volume (accounting for wastage) by the yield of the selected bag size. Different bag sizes have different yields, so ensure you use the correct value.

8. Round Up: Always round up to the nearest whole number when determining the number of bags to purchase. It's better to have a little extra than to run out mid-project.

Concrete Formula calculation:

sing the provided code for a 10 x 10 feet slab with a 4-inch thickness, let's calculate how many concrete bags are required for 80 lbs each:

  1. Slab Length (in feet): 10

  2. Slab Width (in feet): 10

  3. Slab Thickness (in inches): 4

Now, let's calculate:

  • Volume of the slab in cubic feet = Slab Length x Slab Width x (Slab Thickness / 12) = 10 ft x 10 ft x (4 inches / 12) = 10 ft x 10 ft x 0.333 ft = 33.33 cubic feet

  • Volume of the slab in cubic yards = Volume in cubic feet / 27 = 33.33 cubic feet / 27 = 1.234 cubic yards

  • Bags Required (80 lb) = Volume in cubic yards / 0.022 (conversion factor for 80 lb bags) = 1.234 cubic yards / 0.022 ≈ 56.1 bags

Since you can't have a fraction of a bag, you would need approximately 57 bags (80 lb each) of concrete for a 10 x 10 feet slab with a 4-inch thickness.


Mastering concrete calculations is an invaluable skill for anyone involved in construction. With precise measurements and careful planning, you can confidently order the right amount of concrete, ensuring your project progresses smoothly, efficiently, and cost-effectively. Remember, when in doubt, it's wise to consult with a professional or your local concrete supplier for guidance tailored to your specific needs. By following these steps, you'll be well on your way to a successful and well-executed concrete project.

Disclaimer: The concrete calculation information provided is for general reference only. Actual concrete requirements may vary based on project-specific factors and local regulations. It is advisable to consult with a professional for accurate calculations and adhere to safety guidelines during concrete work. The author or Telangana are not liable for any inaccuracies or issues arising from the use of this information.