Measure length and width
For a rectangular driveway, multiply length by width. Split an irregular layout into rectangles and add their areas. Note slopes, steps, curves and areas that need a different finish. Use the same area unit in the calculator and in every quote.
Separate concrete work from site preparation
Ask whether the unit rate includes demolition and disposal, excavation, compacted base, forms, reinforcement, joints, placement, finishing and curing protection. Thickness and reinforcement depend on intended loads and site design; do not use a generic calculator to choose them.
Estimate a budget range
- Enter driveway area and the low/high installed cost per area unit from local bids.
- Add removal, base, drainage or access costs if not already included in the rate.
- Use one currency, add a contingency and compare written scopes line by line.
Check drainage and access before accepting
Water should drain away as intended without creating a hazard or directing runoff onto neighbouring property. Confirm grades, joints, access for delivery equipment and curing restrictions with the contractor. The calculator estimates cost only; it does not design drainage or certify a slab.