How to use it
- Enter the concrete volume in cubic meters (m³).
- Enter the cement dosage in kilograms per cubic meter (kg/m³).
- Press the Calculate button.
- View the total cement kilograms and the number of 50 kg bags.
The Cemex Calculator turns two simple inputs—volume and cement dosage—into the exact amount of cement you must order. Knowing the kilograms lets you match the mix design (20 MPa ≈300 kg/m³, 30 MPa ≈350 kg/m³, 40 MPa ≈400 kg/m³) while the bag count (50 kg each) tells you how many full bags to purchase. For example, 3 m³ at a 350 kg/m³ dosage yields 1 050 kg, which is 21 bags. This eliminates guesswork, reduces waste, and ensures you have enough material on site before the pour starts. The results appear instantly, so you can adjust the mix or order quantities on the fly.
Pro tips
- Add a 5‑10% waste allowance for spillage and compaction loss.
- Round up to the next whole bag to avoid shortfalls.
- Compare the dosage to standard strengths to verify you’re using the right mix.
- Double‑check units; the calculator expects m³ and kg/m³.
Real-life examples
- A small contractor estimating cement for a 2 m³ slab with a 30 MPa mix.
- A DIY homeowner planning a garden retaining wall using a 20 MPa concrete mix.
- A site manager ordering bulk cement for a 10 m³ foundation at 40 MPa strength.
Case study
John, a subcontractor, entered 4 m³ and a 350 kg/m³ dosage. The calculator showed 1 400 kg or 28 bags, so he ordered exactly that amount, avoided a costly extra delivery, and completed the pour on schedule.