Estimated result
Enter measurements and select Calculate.
User-supplied grid arithmetic
Usable dimensions subtract edge cover twice. Bar spaces round up so calculated spacing does not exceed the entered spacing; one bar is then added in each direction.
Structural and code boundary
This tool never recommends diameter, spacing, cover, laps, development length, or required reinforcement. It only estimates grid quantity from supplied assumptions and does not verify ACI, structural, foundation, slab, or local-code adequacy.
Worked example
The editable example values above demonstrate the formula and show every planning assumption used in the result.
Related calculators
This browser-local tool provides a planning estimate, not a purchase guarantee, supplier quote, structural design, engineering specification, permit decision, or code approval.