Construction & Industrial
Concrete volume, brick count, paint coverage, tile estimator, steel weight — practical calculators for builders, contractors, architects, and DIY home projects.
Construction estimation calculators for civil and home building work — concrete (M20/M25 mix), brick count, paint coverage, tile count, plaster, steel weight. Calculations follow IS code standards (IS 10262 for concrete, IS 1786 for steel) used across Indian construction.
Construction
Concrete
Calculate concrete volume for slabs, columns, beams, and footings — plus the cement, sand, aggregate breakdown by mix grade (M10, M15, M20, M25).
Open calculatorTile
Calculate the number of tiles and boxes required for a floor or wall, with wastage allowance for cuts and breakages.
Open calculatorPaint
Calculate litres of paint required for walls and ceiling — accounting for room dimensions, doors, windows, number of coats, and paint coverage rate.
Open calculatorBrick
Calculate the number of bricks required for a wall, including mortar, with wastage allowance. Supports standard Indian and modular brick sizes.
Open calculatorSteel Weight
Calculate the unit weight of steel rebar, plates, pipes, angles, and channels. Uses precise density (7,850 kg/m³) and standard formula d²/162.28 for rebar.
Open calculatorPlaster
Calculate cement and sand required for wall plastering, with adjustable thickness and mix ratio. Standard for both internal (1:6) and external (1:4) plasters.
Open calculatorWhat you can estimate
Material quantities — concrete (cement, sand, aggregate by mix ratio for M15/M20/M25/M30 grades), brick count for any wall area (with mortar volume estimation), paint coverage by area and coats, tile count with breakage allowance, plaster volume by area and thickness, steel weight from diameter and length per IS 1786.
How accurate are estimates
Within ±5-10% for most materials when measured correctly. The calculators include standard waste/breakage allowances (5% for tiles, 10% for cement, 5% for paint). For tendering and final billing, cross-verify with site measurements and the contractor's actual working bill.
Frequently asked questions
How do I calculate cement bags for a slab?
First compute concrete volume (length × width × thickness). Then for M20 (1:1.5:3 ratio), cement portion = 1/(1+1.5+3) = 1/5.5 of the wet volume. Multiplied by 1.54 for dry-to-wet conversion, divided by 0.0347 m³/bag (50 kg). The concrete calculator handles all this for any mix ratio.
How many bricks per square foot of wall?
For a standard 9-inch (230mm) wall using standard 19×9×9 cm bricks, roughly 8 bricks per cubic foot of wall, accounting for 10mm mortar joints. The brick calculator computes total bricks needed for any wall area or volume.
What's the difference between M20 and M25 concrete?
Numbers indicate compressive strength in N/mm² at 28 days. M20 (20 N/mm²) is standard for residential RCC slabs. M25 (25 N/mm²) is used for higher loads — multi-storey, columns under heavy load. Mix ratios: M20 ≈ 1:1.5:3 (cement:sand:aggregate). M25 ≈ 1:1:2.
How do I calculate steel weight?
Per IS 1786, steel weight per meter = D² / 162 where D is diameter in mm. So 12mm bar: 12² / 162 = 0.889 kg/m. For a beam, multiply weight per metre × length × number of bars. The steel weight calculator does this for any diameter and quantity.
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