About the Concrete Mix Design Calculator
What is the Concrete Mix Design Calculator?
This concrete mix calculator estimates materials for nominal mixes by volume, as used on Indian sites. It converts the wet volume to dry volume (×1.54, to allow for voids and bulking) and divides it in the mix ratio.
Cement is converted to 50 kg bags at 1,440 kg/m³, and water uses a typical water–cement ratio for each grade.
How to use the Concrete Mix Design Calculator
- Concrete Grade (nominal mix) (sample: M20 – 1 : 1.5 : 3)
- Wet Concrete Volume (m³) (sample: 1)
- Wastage (%) (sample: 2)
- Press Calculate Concrete Materials (results also refresh as you type). The result card shows the Cement Needed, along with Cement weight, Sand, Sand in cubic feet and Coarse aggregate (20 mm).
Formula used
Material = Wet volume × 1.54 × (Part ÷ Sum of parts)
- Mixes = M10 1:3:6, M15 1:2:4, M20 1:1.5:3, M25 1:1:2
- Cement bags = cement volume × 1,440 ÷ 50
IS 456 permits nominal mixes up to M20; M25 and above should be design mixes (IS 10262).
Worked example
These are the sample values already filled in the calculator above, and the result it returns for them:
| Input | Sample value |
|---|---|
| Concrete Grade (nominal mix) | M20 – 1 : 1.5 : 3 |
| Wet Concrete Volume (m³) | 1 |
| Wastage (%) | 2 |
| Result | Value |
|---|---|
| Cement Needed | 8.23 bags (50 kg) |
| Cement weight | 411 kg |
| Sand | 0.428 m³ |
| Sand in cubic feet | 15.1 cft |
| Coarse aggregate (20 mm) | 0.857 m³ |
| Aggregate in cubic feet | 30.3 cft |
| Water (w/c 0.5) | 206 litres |
| Note | Nominal mix per IS 456; a design mix saves cement on large jobs |
Tips for using the Concrete Mix Design Calculator
- Keep the water–cement ratio low; extra water weakens concrete.
- Cure concrete by keeping it wet for at least 7 days (10 with blended cements).