Mortar mix calculator
Enter the area to build or render: the calculator gives the mortar volume, then the cement (in kg and in 35 kg bags), sand and water for the mix you choose. If you already know the mortar volume, enter it directly: it replaces the area-based calculation.
| 🪣 Mortar volume | |
| 🧱 Cement | |
| 🛍️ Cement bags (35 kg) | |
| 🏖️ Sand | |
| 💧 Water |
Site references for 1 m³ of mortar: the cement content, about 1 m³ of sand (≈ 1.6 t) and ≈ 220 L of water. Mix small batches: mortar that has started to set cannot be "revived" by adding water. For block quantities, see the block calculator and the brick calculator.
Standard mixes, per 1 m³ of mortar
| Mix | Cement | Sand | Water | Typical use |
|---|---|---|---|---|
| 300 kg/m³ | 300 kg | ≈ 1 m³ | ≈ 220 L | Interior renders |
| 350 kg/m³ | 350 kg | ≈ 1 m³ | ≈ 220 L | Block and brick laying |
| 400 kg/m³ | 400 kg | ≈ 1 m³ | ≈ 220 L | Screeds, exposed work |
Remember the simple rule: a standard laying mortar is one 35 kg bag of cement for about 100 litres of mortar at 350 kg/m³. For concrete (with gravel), use the concrete mix calculator instead.