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Concrete
Volume + Rebar 		Rebar Spacing
and Quantity 		Concrete
Pre Mix Bags 		Concrete Columns
and Footings 		Concrete Cutting
Weights ~ Sizes 		Core Drill Angles
Floor AND Wall 		Core Drill Angles
Floor OR Wall
Inch Inch Inch Inch Inch Inch Inch

Calculate Rebar Spacing, Layout and Weight in a Concrete Slab
To calculate Concrete and Total Rebar in a multi sided slab see: Calculate Concrete and Rebar in Multi Sided Slabs

Total Length
Total Width
Spacing ↔ ↕
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Check to allow different spacing in Length ↔ to Width ↕
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Exact Spacing spaces bars at exactly entered centers.
Calculated from either end towards the middle, with middle space adjusted smaller to fit.
Resulting smaller middle space marked red in diagram.
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Equal Spacing adjusts all spaces to fit total length and width evenly, at nearest under or equal to entered spacing.
Edge Clearance
Bar Size
Waste / Overlap
Each Bar Length ft
Cost / Length $
Slab Thickness
Spacing ↔ Scale Rebar

Concrete rebar calculator plan view diagram

Round Measurements To

Running rebar points Running Bar Points (Length - Left to Right):



Running rebar points Running Bar Points (Width - Top to Bottom):



Calculate Rebar Quantity From Total Slab Area and Perimeter

To calculate Total Area of a multi sided slab, first divide the shape into rectangles or squares. (as in example diagram)
Multiply the 2 different side lengths of each rectangle to find individual areas, then add them together to find Total Slab Area.
Add all (outside) side lengths to find the total Slab Perimeter.
Or enter side lengths to draw the shape with the Concrete and Rebar calculator to auto calculate Concrete Volume and Rebar.


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Calculates Approximate Rebar Length.
Does NOT include rebar for Edge or Internal Beam Thickenings.
Total Slab Area 		ft²
Slab Perimeter ft
Rebar Spacing in
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Gap between outer edge of slab and first rebar.
Edge Clearance 		in
Rebar Waste / Overlap %
Each Bar Length in
Cost per Length $
Rebar Size
6m x 2.4m
Rebar From Area Rebar for multi sided slab


Follow Rebar Engineering Specifications. - Incorrect placement can lead to serious concrete structural failures.
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If you need to take full scale measurements directly from your monitor, adjust the size of the diagrams on screen to match a ruler. Does not affect printed sizes. Use keyboard Cursor Keys to fine tune as you adjust scale.
Adjust scale of diagrams to measure 100% scale on screen with a ruler.

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All Inch inputs and dimensions are actual physical finished sizes
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Select output Fraction Precision then Re-Calculate to display.
Fraction Precision
Lumber
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Selected value is automatically copied to clipboard. Select then Paste into text box.
Prec…
0


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