コンクリート計算機

共有リンク

はじめに

Concrete Calculator — Estimate m³ and bags of concrete for any slab. Enter Length (m), Width (m), Thickness (m), Waste (%) to get an instant, accurate result.

計算式

Volume = length × width × thickness, plus a waste percentage allowance; bag count assumes ~2500 kg/m³ density at 40 kg per bag.

ステップごとの説明

Enter the Length (m).
Enter the Width (m).
Enter the Thickness (m).
Enter the Waste (%).
Click Calculate to see your result instantly.

実例

Example: With Length (m) = 5, Width (m) = 4, Thickness (m) = 0.1, Waste (%) = 10, the Concrete Calculator gives Volume M3: 2.2, Volume Without Waste: 2, Bags 40kg: 138.

よくある質問

Why add a waste percentage?

To account for spillage, over-excavation, and uneven forms — 10% is a common default allowance.

What if I use different-sized bags?

Scale the bag count proportionally — the volume figure stays accurate regardless of bag size.

What inputs does the Concrete Calculator need?

You'll need to provide: Length (m), Width (m), Thickness (m), Waste (%). All fields use sensible defaults, so you can see a working example immediately and then adjust the values to match your own numbers.

How accurate is the Concrete Calculator?

The Concrete Calculator applies the formula exactly as calculated — Volume = length × width × thickness, plus a waste percentage allowance; bag count assumes ~2500 kg/m³ density at 40 kg per bag. — so results are precise for the inputs you provide. Accuracy depends on entering correct, realistic input values.

Is the Concrete Calculator free to use?

Yes, the Concrete Calculator is completely free, requires no signup, and runs instantly in your browser.