Construction & estimating · Concrete & reinforcement

Reinforcement quantities & cost calculator

Steel tonnage from a kg/m³ ratio or a bar list, with laps and waste, supply and fix cost.

Standard: kg/m³ ratio or bar list (d²/162 kg/m)

Inputs in the worked example

The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.

Input	Value	Unit
Method	kg per m³ of concrete
Concrete volume (ratio method)	95	m³
Steel ratio	110	kg/m³
Bar list: diameter (mm), number, length (m)	12, 220, 6 16, 96, 9 20, 48, 6 10, 400, 1.6
Laps allowance	7	%
Waste	3	%
Supply	1650	$/t
Fixing	1100	$/t

Diagram for the worked example

Bar mass = d²/162 kg/m
Typical ratios: slabs 80–120, beams 150–250, columns 150–300 kg/m³ (indicative only)
Rates are example inputs only. Replace them with current supplier quotes and local labour rates.

Concrete materials estimate — Cement bags, sand, aggregate and water for site-mixed concrete by ratio, with wastage.
Bar schedule & rebar weight — Reinforcement mass by bar mark, totals by diameter and tonnage to order.
Formwork contact area — Formwork area for slabs, beams, columns and footing edges, ply sheets allowing for re-use, and cost.
Concrete volumes & cost — Volumes for footings, slabs, beams and columns, order quantity rounded to 0.2 m³, trucks and cost.
Earthworks cut & fill — Volumes from cross-section areas, loose and compacted volumes, truck loads and a mass-haul diagram.
Excavation, cart-away & disposal — Excavated bank volume with batters, bulking, backfill retained, truck loads, tonnes to tip and cost.

For preliminary design and education. Check every result against the current standard and your own engineering judgement before use.