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CM into Inches
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Rebar Length Calculator

Calculate total rebar length needed for a grid or layout.

Rebar Length Calculator

Estimate the total linear feet of rebar needed for a grid layout in a slab.

Formula

Length = (L/spacing × W) + (W/spacing × L)

Step-by-step

  1. Compute bars in each direction
  2. Multiply by perpendicular dimension
  3. Sum both directions

Example

20×20 ft slab, 12in spacing = 820 ft total.

FAQ

Does this include overlaps?+

No, add extra for lap splices (typically 30× bar diameter).

What spacing should I use?+

12 inches on center is common for residential slabs.

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