Concrete & Mortar Calculator

Estimate concrete volume or premixed mortar bags

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Results

Net volume2 m³
Volume including waste2.2 m³
Premix bags110

Bag count applies only to premixed mortar/concrete with a stated yield, not raw cement mixed with sand and aggregate. The 20-liter yield is illustrative; use the label.

Formula and method

Volume in m³ = width × length × thickness in cm ÷ 100. Bags = round up(volume including waste × 1,000 ÷ liters yielded per bag).

Worked example

A 4 × 5 m area, 10 cm thick, needs 2 m³ or 2.2 m³ with 10% waste. Premix yielding 20 liters per bag requires 110 bags.

Frequently asked question

Is this the raw cement bag count for mixing on site?

No. It applies to premixed products with a stated yield. On-site mixing requires separate cement, sand, aggregate and water proportions.