Reference formulas and worked examples below keep their stated units. Monetary examples use USD; dimensional examples use US customary units unless labeled otherwise. Metric calculator inputs are converted to these reference units before calculation. Choosing another currency does not convert example amounts or exchange money.
How to use this paver base calculator
Start with the first rectangle. Add up to 19 more areas below; each has its own gravel and sand depths. Shared allowances apply to all areas.
How the calculation works
Area = length × width. Each layer’s cubic feet = area × depth in inches ÷ 12.
Gravel volume includes the compaction allowance and waste allowance. Sand includes waste only. Divide cubic feet by 27 for cubic yards.
Sum adjusted volumes across all rectangles, then divide gravel and sand by their respective bag yields and round each total up once.
Worked example
For 10 × 20 ft, 4 in of gravel and 1 in of sand, with both allowances at 0%, the gravel is 66.67 cu ft (2.47 cu yd) and the sand is 16.67 cu ft (0.62 cu yd). At 2 cu ft per bag, that is 34 gravel bags and 9 sand bags.
Limits and assumptions
A material takeoff for up to 20 non-overlapping rectangles. It does not choose a safe base depth, account for irregular edges, specify drainage, or replace a supplier’s density and bag yield.
Frequently asked questions
Does the calculator include compaction?
Yes, when you enter an extra gravel percentage. The default is 0% so no unstated compaction factor changes your order.
Why are gravel and sand separate?
They are different layers and may be supplied in different bag sizes or bulk quantities. Read each result separately before ordering.
Can I calculate an L-shaped patio?
Yes. Enter the first rectangle, then use Add another area for the remaining sections. The calculator sums each material before rounding bags. Do not count an overlap twice.