Calculate exactly how much gravel your project requires. Follow our simple formula, check the reference tables, and get the right amount the first time.
To figure out how much gravel you need, measure the length and width of your area in feet, choose a depth in inches, and apply this formula:
Cubic Yards = Length (ft) × Width (ft) × Depth (in) ÷ 324
For example, a 12 × 10 foot patio at 3 inches deep needs: 12 × 10 × 3 ÷ 324 = 1.11 cubic yards. To convert to tons, multiply by 1.35: 1.11 × 1.35 = 1.50 tons.
That one formula works for any rectangular area. The number 324 is a constant that combines the conversion from inches to feet (12) with the conversion from cubic feet to cubic yards (27): 12 × 27 = 324.
Want to skip the math? Use our free gravel calculator to get instant results for any dimensions.
Follow these four steps to determine the exact amount of gravel for your project. This method works for patios, driveways, walkways, shed bases, french drains, and any other application.
Use a tape measure to find the length and width of the area you plan to cover, in feet. For irregular or L-shaped spaces, break the area into separate rectangles and measure each one individually. You will calculate each section separately and add them together at the end.
Select the appropriate gravel depth for your project type. Driveways need 4 to 6 inches, walkways require 2 to 3 inches, patios work well at 3 to 4 inches, and french drains call for 12 inches. See our gravel depth guide for detailed recommendations by project.
Multiply length × width × depth (in inches), then divide by 324. The result is your volume in cubic yards, which is the standard unit suppliers use for pricing and delivery.
Formula: L (ft) × W (ft) × D (in) ÷ 324 = cubic yards
Many suppliers sell gravel by the ton rather than the cubic yard. To convert, multiply your cubic yards by the density factor for your material. Standard gravel weighs about 1.35 tons per cubic yard. Check the gravel weight chart for specific materials.
Formula: Cubic yards × 1.35 = tons (for standard gravel)
The table below shows how much gravel common projects require. These are calculated using the standard formula and assume typical recommended depths for each application.
| Project | Size | Depth | Cu. Yd. | Tons |
|---|---|---|---|---|
| Patio (10×12) | 120 sq. ft. | 3" | 1.11 | 1.50 |
| Driveway (50×10) | 500 sq. ft. | 4" | 6.17 | 8.33 |
| Shed Base (10×12) | 120 sq. ft. | 4" | 1.48 | 2.00 |
| Walkway (30×3) | 90 sq. ft. | 2" | 0.56 | 0.76 |
| French Drain (50×1) | 50 sq. ft. | 12" | 1.85 | 2.50 |
Tons calculated using standard gravel density of 1.35 tons per cubic yard. Actual tonnage varies by material.
The amount of gravel you need per square foot depends entirely on depth. A deeper layer uses proportionally more material. This table shows the cubic yards and approximate weight of gravel per square foot at three common depths.
| Depth | Cu. Yd. per Sq. Ft. | Lbs per Sq. Ft. |
|---|---|---|
| 2 inches | 0.006 | ~17 lbs |
| 3 inches | 0.009 | ~25 lbs |
| 4 inches | 0.012 | ~33 lbs |
To find the total gravel for your project, multiply the per-square-foot value by your total area. For 200 square feet at 3 inches deep: 200 × 0.009 = 1.80 cubic yards.
For a complete lookup table showing how much area different quantities of gravel cover, see our gravel coverage chart.
No matter how carefully you measure, real-world conditions introduce variability. The ground is rarely perfectly level, edges need extra material, and gravel compacts as it settles into place. Professional landscapers and contractors routinely add 10% to their calculated quantities.
Here is why the extra 10% matters:
Running short mid-project means a second delivery, which adds cost and delays. A small surplus is always preferable. Leftover gravel can be used for future repairs or other landscaping tasks.
When ordering gravel, you may need to convert between different units. Here are the most common conversions:
Need to convert square feet to cubic yards? Use our square feet to cubic yards converter or the full cubic yards calculator for more options.
Enter your project dimensions and get instant results for cubic yards, tons, and estimated cost.
Calculate Exact Amount →For a 10×10 ft area (100 sq. ft.) at 3 inches deep, you need 0.93 cubic yards or about 1.26 tons of gravel. At 4 inches deep, you need 1.23 cubic yards or 1.66 tons. Use the formula: 10 × 10 × depth (inches) ÷ 324 = cubic yards.
First calculate cubic yards using the formula Length × Width × Depth (inches) ÷ 324. Then multiply cubic yards by 1.35 to get tons for standard gravel. For example, 2 cubic yards × 1.35 = 2.70 tons. Different materials have different densities, so the tons-per-cubic-yard conversion factor varies.
Yes, always order 10% more gravel than your calculation shows. This accounts for waste during spreading, settling over time, uneven ground, and slight measurement variations. Running short mid-project is more costly than having a small surplus.
The amount of gravel per square foot depends on depth. At 2 inches deep you need about 0.006 cubic yards per sq. ft. (roughly 17 lbs). At 3 inches deep, 0.009 cu. yd. per sq. ft. (about 25 lbs). At 4 inches deep, 0.012 cu. yd. per sq. ft. (about 33 lbs). Multiply the per-square-foot figure by your total area to get the total volume needed.