PEA GRAVEL
Pea gravel calculator
Cubic feet of pea gravel = square feet × depth in inches ÷ 12, and cubic yards = square feet × depth in inches ÷ 324. Pea gravel is a volume product like any other aggregate, so the arithmetic is the same as for mulch or topsoil — what differs is the package and the weight.
Worked example
A 200 sq ft path at 2 inches: 200 × 2 ÷ 12 = 33.33 cubic feet, which is 33.33 ÷ 27 = 1.23 cubic yards.
In bags, divide by the bag volume and round up. Pea gravel is commonly sold in 0.5 cubic foot bags — often labelled as a 50 lb bag — so 33.33 ÷ 0.5 = 66.7, which is 67 bags. Buying it by the yard instead is 1.23 cubic yards, and most yards sell in whole or half yards, so that becomes a 1.5 yard order unless they will split it.
Why the bag count on pea gravel surprises people
Half-cubic-foot bags are small. A path that looks like a modest afternoon's work is over sixty bags, and each one weighs about fifty pounds. Two things follow:
- Bagged pea gravel is usually for small areas. Borders, plant surrounds, a narrow strip. Past a couple of hundred square feet the bag count stops being practical.
- Bulk is priced and delivered by volume. Compare by converting the bag price to price per cubic foot, the way the yard price check does for mulch.
Tons: the honest answer
Pea gravel is often quoted by weight, and converting your cubic yards into tons needs the density of that specific aggregate. Pea gravel is a gradation, not a single material — the rock it is crushed from, the size range and the moisture all move the number, and a density borrowed from a different product can be wrong enough to matter on a delivery.
So: calculate cubic yards here, then ask the supplier for their pounds per cubic yard for the product you are buying, or ask them to quote in cubic yards. This page will not print a tonnage figure it cannot stand behind.
Depth for pea gravel
Pea gravel is rounded and moves underfoot, which is why it is common on paths and borders and unusual as a driveway surface. Depth is a design decision that depends on what is underneath and what will cross it — a decorative dressing, a walking path and a drainage layer are three different depths. Use the depth your project calls for; the calculator only multiplies.
Before you order
- Put a weed membrane down first if the pea gravel is decorative — rounded stone on bare soil migrates and weeds come through. Fabric does not change the volume you need.
- Edge the area. Pea gravel does not interlock; it spreads unless something holds it.
- Check the delivery weight and access before choosing bulk.
- Decide loose versus compacted depth if the gravel is going under anything.
Related calculators
Gravel calculator for the general aggregate case and the tonnage method · How much gravel for a driveway · Mulch calculator for the same volume arithmetic on a lighter material.
Sources: Bag volume is 0.5 cubic feet / 50 lb, the common retail size for bagged pea gravel. The arithmetic is from the definitions 1 cubic yard = 27 cubic feet and 1 foot = 12 inches.