Free Tools
Element Reinforcement Calculator (Rebar + Stirrups)
Calculate main rebar plus stirrup quantity & weight for an already-determined design. A quantity estimate — not a strength check.
Main reinforcement
Stirrups
Advanced settings▾
Concrete cover & stirrup hook length.
Prices (optional)
Quantity, not a strength verdict
This is an early estimate based on common rules of thumb, NOT a structural calculation. The truly safe sizes/values depend on load, soil conditions, and seismic risk at your site, and MUST be calculated by a certified structural engineer (also a PBG permit requirement). Do not build structural elements based on this calculator alone.
Reinforcement requirement
Calculates QUANTITY for an already-determined design. The calculator does NOT judge whether the reinforcement is strong enough — that's an engineer's domain. Excludes laps/splices.
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Leave your contact and a Luxury Art engineer will help calculate & design structural reinforcement for a PBG permit. Free initial consultation.
How to calculate reinforcement
Main bars + stirrups
Main bar weight = bar count × length × weight per meter. Stirrups are computed from count (length ÷ spacing + 1) times each stirrup's perimeter (from element dimensions + hooks). Both sum to total weight.
For an EXISTING design
This calculator uses the diameter, count, and stirrup spacing YOU set. It computes the rebar quantity and weight — it does not judge whether that reinforcement is strong enough for the load.
Adequacy = an engineer's domain
Determining safe diameter, count, and stirrup spacing depends on the moments and forces acting on the element — a structural analysis result by a certified engineer, and a PBG permit requirement.
FAQ
Frequently asked questions
How do I calculate beam rebar needs?
Set the main reinforcement (diameter and count) and stirrups (diameter and spacing), plus the beam length. Main bar weight = count × length × weight/m; stirrup weight comes from stirrup count × perimeter per stirrup × weight/m. The calculator does all of this automatically.
How do I calculate the number of stirrups?
Stirrup count ≈ element length ÷ stirrup spacing + 1. Example: a 4 m beam with stirrups every 15 cm (0.15 m) → about 27. Each stirrup length comes from the element's section perimeter minus cover, plus hook length.
Does this determine if my rebar is strong enough?
No. This calculator only computes the QUANTITY and weight of rebar for the reinforcement you already set. Judging whether it's strong enough for the load is a structural analysis result by a certified engineer — don't use the calculator to decide that.
Are lap/overlap lengths included?
No. Splice/overlap lengths and development details depend on design and aren't added automatically. For precise needs, add overlap per your working drawings or ask the Luxury Art team for help.
How do I estimate the rebar cost?
Enter the rebar price per kg and the calculator multiplies it by total weight. You can also press "Add to BoQ" to send the result to the BoQ calculator and combine it with other work.
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Luxury Art — Structural & Architecture Design
You have the early estimate. The structural calc needs an expert.
The calculator here is only an early estimate — decisions on structural size & strength must be calculated by a certified engineer, and are also a PBG permit requirement. Luxury Art provides certified structural & architecture design, professional cost planning, and design-build & construction management.
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