Engineering & Construction
Rebar Spacing Calculator
Count bars from the clear distance inside the cover and a centre-to-centre spacing.
Free forever.
Count = floor((span − 2 × cover) ÷ spacing) + 1. Bars start at the cover and keep that spacing. The last bar reaches the far cover only when the clear distance divides exactly.
Result
Press Calculate.
Result
Press Calculate.
How to use the Rebar Spacing Calculator
- Enter the span and the cover at each side.
- Enter the centre-to-centre spacing.
- Read how many bars fit, and how far the last bar stops short of the far cover.
Questions
How is the count worked out?
floor((span − 2 × cover) / spacing) + 1.
Why is the last gap sometimes smaller?
The bars are placed from the cover at the spacing you set. The remainder stays inside the far cover.
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