Concrete Slab and Screed Calculator

Enter the slab length, width and thickness. The calculator returns the concrete volume, the number of bags of dry mix and the estimated cost, with a reserve for spillage.

7-in-1 Pro Calculators

±1% Formula Accuracy

EN/RU/ES 3 Languages

Wall & Ceiling Paint Estimator

Room Dimensions

Room Length m

Room Width m

Wall Height m

Include Ceiling?

Doors, Windows & Coverage

Number of Doors

Number of Windows

Number of Coats

Paint Coverage m²/L

Container Size L

Price per Container $

Ceramic & Porcelain Tile Estimator

Surface Dimensions

Area Length m

Area Width m

Tile Size, Waste & Packaging

Tile Length cm

Tile Width cm

Grout Joint Gap mm

Cutting / Waste Reserve %

Coverage per Box m²

Price per Box $

Laminate & Hardwood Flooring Estimator

Room Floor Dimensions

Room Length m

Room Width m

Plank Size, Pattern & Packaging

Plank Length cm

Plank Width cm

Installation Pattern (Waste %)

Area per Pack m²

Price per Pack $

Underlayment Price per Area $

Wallpaper Rolls & Paste Calculator

Room Dimensions

Room Length m

Room Width m

Wall Height m

Roll Dimensions & Pattern Repeat

Roll Width cm

Roll Length m

Pattern Repeat (Offset) cm

Number of Doors

Number of Windows

Price per Roll $

Drywall Sheets, Framing & Screws Estimator

Structure Type & Sheet Dimensions

Construction Type

Single Sheet Area m²

Wall / Room Length m

Height (or Ceiling Width) m

Price per Drywall Sheet $

Concrete Slab, Screed & Bags Calculator

Slab / Pour Dimensions

Slab Length m

Slab Width m

Thickness / Depth cm

Reserve, Pre-Mix Bags & Pricing

Spillage / Grade Reserve %

Dry Mix Bag Size kg

Price per Bag $

Appliance Electricity Cost Calculator

Appliance Power & Usage Schedule

Appliance Name

Power Consumption W

Hours Used per Day h

Days Used per Month 1–31

Electricity Rate (per kWh) $

Live Calculation Summary

Paint required

9.1 L

4 cans × 2.5 L

Net Requirement 88% / 12% Reserve / Deductions

Compare Current Material Prices:

Home Depot Lowe's Amazon DIY Leroy Merlin

My Renovation Shopping List & Budget

Category / Calculation	Required Quantity	Estimated Cost

Frequently asked questions

How do I calculate the volume of a concrete slab?

Multiply length by width by thickness, all in the same unit. For example, 4 m × 3 m × 0.1 m is 1.2 m³. The calculator converts thickness from centimeters or inches for you.

How many bags of concrete do I need per cubic meter or yard?

One cubic meter needs roughly 80 bags of 25 kg dry mix (or 40 bags of 50 kg). One cubic yard needs roughly 45 bags of 80 lb mix.

How thick should a concrete slab be?

A garden path or patio is usually 7–10 cm thick, a garage floor 10–15 cm. Heavy loads need a thicker slab with reinforcement.

How much extra concrete should I order?

Order 5–10% more than the calculated volume to cover uneven ground, spillage and formwork that is not perfectly level. Running short mid-pour leaves a weak cold joint.