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Craft & DIY

Concrete Mix Calculator

Calculate the cement, sand, gravel and water you need for your concrete project by volume and mix type.

Depending on the application, concrete needs different mix ratios. Choose your required volume and concrete type to calculate cement, sand, gravel and water needs.

m³
w/z
Lower = stronger but harder to work with. Typical: 0.50 standard, 0.45 watertight, 0.60 lean concrete.
–
Cement / sand / gravel / water

Pro tips

  • For load-bearing elements always use ready-mix concrete or structural advice.
  • Too much water significantly weakens the final strength.
All calculations are non-binding estimates provided without guarantee. For safety-relevant decisions (e.g. pool chemistry), please consult a professional.

Frequently Asked Questions

How much cement do I need per cubic meter of concrete?

Depending on the concrete type, usually 150-350 kg of cement per m³ – lean concrete needs the least, structural concrete for load-bearing elements needs the most.

What does the water-cement ratio mean?

The w/c ratio describes the proportion of water to cement – a lower ratio produces stronger but harder-to-work concrete.

What concrete type is right for a foundation?

Standard concrete is usually enough for regular footings and slabs; load-bearing elements like columns or floor slabs need structural concrete.

How long does concrete need to cure?

Concrete is usually walkable after about 24-48 hours, but it only reaches full strength after around 28 days.