Stone & Gravel Calculator
Calculate stone volume, weight, and cost instantly.
Example: A 20 ft × 25 ft garden bed = 500 sq ft
Instant Results
💡 Did You Know?
1 cubic yard of mulch covers approximately:
162
sq ft @ 2"
108
sq ft @ 3"
81
sq ft @ 4"
🌳 Most homeowners choose 3" depth for trees, shrubs, and general landscaping.
Ready to calculate?
Enter your area or dimensions to get:
✓ Cubic yards required
✓ Bag counts
✓ Weight estimates
✓ Cost comparisons
How to Calculate Stone, Gravel, and River Rock
Figuring out how much stone or gravel you need doesn't have to involve guesswork. Whether you're building a pathway, laying a new driveway, or creating decorative river rock beds, our free stone and gravel calculator gives you precise cubic yard estimates, bag counts, and weight totals in Tons in seconds.
How the Gravel Calculator Works
The math behind every cubic yards of gravel calculator is straightforward: multiply the area of your garden bed (in square feet) by the desired depth (in inches), then divide by 324. Our tool automates this formula and extends it with real-world features no spreadsheet can match — including support for circles, triangles, tree rings, trapezoids, and L-shaped beds. Select your shape, enter your measurements, choose a depth, and your results appear instantly.
For quick estimates, enter your total square footage directly. A typical 20 ft × 25 ft garden bed covers 500 sq ft. At the standard gravel pathway depth of 2 inches, that's 3.09 cubic yards — which weighs approximately 4.17 Tons.
Choosing the Right Stone Depth
Depth is the single biggest factor in how much stone you'll buy. Most landscaping professionals recommend three standard depths: 2 inches for walking paths and decorative areas, 3 inches for general-purpose landscaping, and 4 to 6 inches for driveways and French drains.
Understanding Tons vs. Cubic Yards
While mulch is almost exclusively sold by volume (cubic yards), bulk stone and gravel are frequently sold by weight (Tons). The conversion depends entirely on the type of stone. A cubic yard of typical crushed stone or river rock weighs about 2,700 lbs (1.35 Tons). Lightweight stones like lava rock weigh less than half that amount. Our calculator automatically adjusts the Tons based on the exact material you select.
TheMulchCalculator.com is a free landscaping estimator tool designed for homeowners, DIY gardeners, landscapers, and garden centers. No signup required. No ads. Just fast, accurate math.
Frequently Asked Questions
How do you calculate stone or gravel?
To calculate stone or gravel, multiply the length × width of your area (in feet) to get square footage. Then multiply by the desired depth (in inches) and divide by 324 to get cubic yards. Formula: (Length × Width × Depth in inches) ÷ 324 = cubic yards of stone needed.
How much does a yard of gravel weigh?
A cubic yard of typical gravel or river rock weighs about 2,700 to 2,800 pounds (1.35 to 1.4 Tons). Lightweight stones like lava rock weigh much less, around 1,200 pounds per cubic yard.
How many tons of gravel do I need?
Generally, one cubic yard of gravel equals about 1.35 to 1.4 Tons. Calculate your cubic yards first, then multiply by 1.35 to estimate the total Tons required.
How deep should I lay river rock or gravel?
For walking paths, a depth of 2 inches is standard. For general landscaping, 3 inches provides good coverage. For driveways or heavy drainage areas, a depth of 4 to 6 inches is recommended to support weight and water flow.
How much area does a ton of gravel cover?
One ton of gravel (about 2,000 lbs) covers roughly 80 to 100 square feet at a depth of 2 inches. At 3 inches deep, it will cover about 60 square feet.
Is bulk gravel cheaper than bags?
Yes, significantly. Bagged stone is very expensive per cubic yard (often over $150/yd equivalent). Buying bulk gravel by the cubic yard or ton from a landscape supply yard is usually 50-80% cheaper for projects requiring more than a cubic yard.