Paver Base Calculator

How the number is worked out

area = length × width
gravel (ft³) = area × gravel depth ÷ 12
sand (ft³) = area × sand depth ÷ 12
cubic yards = cubic feet ÷ 27
dig depth = gravel + sand + paver thickness
soil to remove = area × dig depth ÷ 12 ÷ 27

The gravel depth you enter is the depth after compacting. Loose gravel packs down when you tamp it, so you'll spread more than the finished depth; the extra box is there if you want to allow for that. We don't put a number on it because we haven't found a published figure we can cite.

How deep to dig for pavers

Dig depth is the three layers stacked: gravel, then sand, then the paver itself. The two sources we cite don't give the same layer depths:

QUIKRETE's paver sand data sheet calls for 2 to 4 in (50 to 100 mm) of gravel or crushed rock as the base, then 1 to 2 in (25 to 50 mm) of paver sand over the compacted base (No. 1150). Belgard says the base “should be between 4 and 6 inches deep,” with at least 1 in of bedding sand, and notes that base depth depends on soil type and use (installation guide).

QUIKRETE's range is what you place before compacting and Belgard's is the compacted layer, so the two don't line up exactly. On paper, 4 in is the only gravel depth inside both ranges, and 1 in of sand meets both — that is why the calculator starts at 4 and 1. We don't pick between them; if your pavers come with their maker's instructions, those are the ones to follow.

Worked examples

A 12 ft × 12 ft patio with 4 in of gravel, 1 in of sand and pavers 2.375 in thick:

• Area: 144 ft²
• Gravel: 144 × 4 ÷ 12 = 48 ft³ = 1.78 yd³
• Sand: 144 × 1 ÷ 12 = 12 ft³ (0.44 yd³)
• Dig depth: 4 + 1 + 2.375 = 7.375 in
• Soil out: 144 × 7.375 ÷ 12 ÷ 27 = 3.28 yd³

Note that 7.375 in is deeper than the 4 to 7 in QUIKRETE gives for the dig. That is because this example takes the top of QUIKRETE's gravel range (4 in) and then adds the paver; QUIKRETE's own layer ranges add up to 3 to 6 in before the paver goes on. We've left the numbers as they are so you can see where the difference comes from rather than have it hidden.

The same patio with Belgard's deepest base, 6 in of gravel, same sand and pavers:

• Gravel: 144 × 6 ÷ 12 = 72 ft³ = 2.67 yd³
• Sand: unchanged, 12 ft³
• Dig depth: 6 + 1 + 2.375 = 9.375 in
• Soil out: 144 × 9.375 ÷ 12 ÷ 27 = 4.17 yd³

Two more inches of base on 144 ft² means 24 ft³ (0.89 yd³) more gravel coming in and 24 ft³ (0.89 yd³) more soil going out. The soil you dig out is more than the gravel you bring in either way. Plan where it goes before you rent the equipment.

Why there's no tons figure by default

Gravel is often sold by the ton rather than by the yard, and the conversion depends on the stone, its size and how wet it is. We looked for a published density we could quote word for word and didn't find one we'd stand behind, so the calculator only converts to tons when you enter your supplier's figure.

Even QUIKRETE lists its All-Purpose Gravel by weight only, in 50 lb (22.6 kg) bags at 56 bags per pallet, with no cubic-foot yield on the data sheet (Sand & Gravel Products). So we can't turn cubic yards into a bag count for it either. Ask the store or the yard what volume a bag or a ton fills.

Questions people ask

What's the difference between paver base and paver sand?

They are two separate layers. The base is compacted gravel or crushed rock that carries the load: QUIKRETE calls it “an underlayment base,” Belgard a “compacted granular aggregate.” The sand is a thin bed on top of it that the pavers are set into and leveled on. The calculator gives them separately because you buy them separately.

How many inches of gravel under pavers?

QUIKRETE: 2 to 4 in. Belgard: 4 to 6 in, depending on soil and use. QUIKRETE’s figure is what you “Place” before you compact it; Belgard’s is the “compacted granular aggregate” itself. Either way, the depth you enter here is the finished one.

How deep should paver sand be?

QUIKRETE: 1 to 2 in. Belgard: at least 1 in.

How much sand do I need for pavers?

Area in square feet × sand depth in inches ÷ 12 gives cubic feet; divide by 27 for cubic yards. QUIKRETE's data sheet calls for 1 to 2 in of paver sand (No. 1150), so a 144 ft² patio takes 12 ft³ (0.44 yd³) at 1 in and 24 ft³ (0.89 yd³) at 2 in. That is the bedding layer only; the calculator doesn't count sand swept into the joints after the pavers are down.

How much paver base do I need for a 10×10 patio?

100 ft² at 4 in of gravel is 100 × 4 ÷ 12 = 33.33 ft³, or 1.23 yd³. The 1 in sand bed is 100 × 1 ÷ 12 = 8.33 ft³ (0.31 yd³).

Can I use this for a driveway?

For the arithmetic, yes. For the depths, no: neither source above gives driveway figures, and we don't have one to cite. A driveway base should be designed for the vehicles and the soil.

What this calculator is not for