Reinforcement steel calculator
Enter the concrete volume and pick the element type, and the tool gives you a range rather than a number. Steel quantity is set by the structural drawings: span, load and detailing move it a long way, and a single figure here would be false precision.
The volume of the element in cubic metres. Work it out on the concrete calculator if you do not have it.
Turn this off if you have a bar-bending schedule: it already includes laps, and counting them twice inflates the order.
Default price from the Saudi Arabia market — checked August 2026 — change it to the quote you were given.
🔒 Worked out in your browser — nothing is sent to a server
Estimated steel weight
126 – 189 kg
For a Slab
Breakdown
| Steel ratio | 80 – 120kg/m³ |
| Low end | 126kg |
| High end | 189kg |
| In tonnes | 0.13 – 0.19 |
| Midpoint | 158kg |
| Estimated cost | 365.40 – 548.10 |
The midpoint is for outline budgeting only. Do not order steel against it and do not price a contract on it: the only binding figure is the bar-bending schedule from the structural engineer.
The ratios used are budgeting figures drawn from ordinary practice, not a design. Do not build to them and do not submit a binding quotation on them. Get the bar-bending schedule before you buy.
How it's calculated
Steel content is measured in kilograms per cubic metre of concrete. The ratio changes with the element: a footing spreads its load over a large area and needs relatively little steel for its volume, while a column concentrates the whole load into a small section and needs twice as much or more.
So the tool asks for the element type first, then multiplies the volume by the low and high ends of the ratio. The answer is a range, and that is the honest shape for it: the real design can sit anywhere inside depending on span, load and detailing requirements.
The wastage option adds 5 percent for laps, offcuts and bends. If you have a bar-bending schedule from the structural engineer, turn it off: the schedule already counts laps inside the bar lengths, and adding them again inflates the order.
- Weight = concrete volume × steel ratio per m³
- The ratio comes from the element type, and columns are always above slabs
- The answer is a low and a high, never a single number
- The wastage option adds 5 percent for laps and offcuts
- Tonnes = weight in kilograms ÷ 1000
Worked example
A 1.5 m³ slab at 80 to 120 kg per cubic metre, with 5 percent added:
- Low end: 1.5 × 80 = 120 kg
- High end: 1.5 × 120 = 180 kg
- With 5 percent wastage: 126 to 189 kg
- In tonnes: 0.13 to 0.19
- Midpoint for budgeting: 158 kg
Order against the high end if you are buying before the drawings arrive. Running short of steel stops the pour, while a surplus gets used on the next element.
FAQ
Why will the tool not give me one number?
Because one number here would be a polite lie. Steel content is not a function of concrete volume, it is a function of span, load and detailing. Two elements of identical volume can differ by a factor of two. The range tells you what is plausible; only the drawings tell you what is right.
Why are columns higher than slabs?
A column gathers the loads of every floor above into a small section, and needs dense longitudinal bars with closely spaced links, especially at the ends. A slab spreads its load over a wide area and gets by with a lighter mesh. The gap between 150-250 for a column and 80-120 for a slab reflects exactly that.
When should I turn the wastage off?
When you have a bar-bending schedule. The schedule gives bar lengths including laps and bends, so adding 5 percent on top double counts. Leave it on for an outline estimate made before the drawings arrive.
Does the price include cutting and fixing?
No. The default is the mill price of plain bar by the tonne. Cutting, bending, fixing and tying are separate labour items, usually priced per tonne as well and added on top of the material. Change the field if your quote is for supply and fix together.
Can I use this figure in a quotation?
No. Use it to size a budget or to sanity-check a quote you have received. Anything binding has to be built on the bar-bending schedule from the structural engineer, because the gap between the two ends of the range can be fifty percent.
Related tools
Sources
✓ Reviewed September 2026- Steel ratios in kilograms per cubic metre are drawn from ordinary residential practice. They are budgeting and ordering figures, not a design, and never a basis for construction
- The answer is given as two ends rather than one number, because reinforcement is set by the structural drawings: span, load and detailing move the figure within the range and sometimes outside it
- A 5 percent allowance for laps, offcuts and bends, which can be switched off because bar-bending schedules already account for laps
- The default price is dated in the pricing config and shown as an editable field. Steel is the most volatile material on any site because it follows the global billet market
Assumptions used
- Steel content per cubic metre of concrete, as a range. The actual figure comes from the structural drawings and depends on span, load and seismic detailing; these bands are for ordering and budgeting, never for building.
- Offcuts, laps and bends. Detailed bar-bending schedules already include laps, so do not add this twice.