Rebar Quantity Calculator.
Estimate reinforcement bar count, total length and weight for a simple slab grid.
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Use this result as a planning estimate, then create controlled Zektrx records for tasks, templates, evidence, actions, pricing and delivery.
Instant Results
Estimated bars
27bars
Total bars across both directions.
Total bar length
49.5m
Total rebar length including waste.
Estimated weight
44.0kg
Estimated rebar weight.
Explanation
What this calculates
The grid is calculated in both directions and waste is applied to total length before estimating weight.
Formula
Bars each way = floor(span / spacing) + 1; weight per metre = diameter2 / 162
Inputs are validated on screen and converted where unit options are available.
Worked Example
Example result
A 6 m x 4 m slab at 200 mm spacing with 12 mm bar needs about 274 m of bar including 10% waste.
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Templates
Document the result
Software
Turn it into a workflow
Learn before you act.
More related articles are planned for this section.
Calculator questions.
Does this design reinforcement?
No. It estimates quantities only. Reinforcement must follow engineering design.
Does it include laps and bends?
Only through the waste allowance. Add project-specific laps, bends and chairs separately.
Next Step
Make estimates part of the job record.
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