What is a gravel calculator?
A gravel calculator is a volume calculator that estimates the amount of gravel, crushed stone, or aggregate needed to cover an area to a desired depth. Enter your length and width, set the depth in inches or feet, choose a gravel type, and the tool returns the volume of gravel in cubic yards or cubic meters — plus tonnage so you can order by weight if your supplier prices by the tonne.
Use our gravel calculator for landscaping materials, driveway resurfacing, walkway beds, drainage fills, and construction projects where a precise material estimate prevents costly over-orders or mid-project shortages.
How the calculator works
The free gravel calculator runs three steps to calculate gravel volume and weight from your project dimensions:
Volume (ft³) = Length × Width × Depth (in feet)
Convert depth from inches to feet by dividing by 12 before multiplying. The inch calculator helper in the tool handles this automatically.
Cubic yards = Volume (ft³) ÷ 27
Suppliers quote gravel by the cubic yard, so this conversion is what you bring to the order desk. One cubic yard of gravel fills roughly a 3 × 3 × 3 ft space.
Weight = Cubic yards × Gravel density (tons/yd³)
Multiplying the volume by gravel density gives you the weight of the material. Density varies by type — use the presets or enter your supplier's figure.
To calculate the total cost, multiply the cubic yards or tonnes by the price per unit quoted by your supplier. Add 5–15% for compaction and extra material — gravel settles after delivery and you want to know the approximate final coverage before placing the order.
How to use this gravel calculator
- 1
Enter area dimensions
Input length and width in feet for rectangular areas. Use the circular or irregular mode for round features and landscape beds. For a 10 feet wide driveway, just enter the width and the total feet long to get started.
- 2
Set the desired depth
Enter the depth in inches using the inch calculator helper or type directly in feet. Driveways typically need 4–6 inches; walkways and landscape beds work well at 2–3 inches.
- 3
Select the type of gravel
Choose from pea gravel, crushed stone, river rock, bank run, decomposed granite, lava rock, marble chips, or cobble. Each preset loads the correct gravel density so the weight estimate stays accurate.
- 4
Choose output units
Toggle between cubic yard and tonne output, or show both. Use the calculator to determine how many tons your order will weigh if your supplier prices by weight rather than volume.
- 5
Review and adjust for compaction
Use the calculator results as your baseline order quantity, then add your compaction allowance. The tool flags the recommended percentage based on gravel type so you always order enough to achieve a solid foundation.
Different types of gravel and when to use them
The type of gravel you choose affects both the gravel density used in the weight calculation and the suitability of the material for your project. Here are the most common options:
Pea gravel
Walkways, garden beds, decorative top layers. Rounded and smooth — comfortable underfoot but does not compact into a solid foundation.
Crushed stone
Driveways, base layers, and hardscape. Angular rock fragments lock together under load, making it the go-to for structural fills.
Bank run aggregate
General fill and subbase. Mixed aggregate straight from the bank, including sand and fines — good for compaction beneath other layers.
River rock
Drainage channels and decorative landscape borders. Smooth, rounded, and available in larger sizes than pea gravel.
Decomposed granite
Pathways and low-traffic landscape areas. Compacts well and gives a natural, earthy appearance — also used as topsoil amendment.
Lava rock & marble chips
Decorative landscape beds. Low density means a cubic yard of gravel goes further by weight — factor this into your tonne estimate.
Example calculations
Driveway — 10 ft wide × 50 ft long × 4 in deep
Volume = 10 × 50 × (4/12) = 166.7 ft³ ÷ 27 = 6.2 cubic yards. Using crushed stone at ~1.4 tons/yd³, that's roughly 8.7 tons of gravel needed to complete the base layer. Add 10% compaction allowance and order 9.5 cubic yards.
Walkway — 3 ft wide × 20 ft long × 2 in deep (pea gravel)
Volume = 3 × 20 × (2/12) = 10 ft³ ÷ 27 = 0.37 cubic yards. Pea gravel at ~1.3 tons/yd³ gives approximately 0.5 tons. A single partial yard order covers this walkway with room to spare for the area you need to fill around the edges.
Landscape bed — irregular area, 3 in depth
Divide the bed into simple rectangular sections, calculate each volume separately using the volume calculator, then sum the cubic yard totals. Use our gravel calculator's irregular mode to handle this automatically for gravel needed for landscaping and hardscape borders.
Frequently asked questions
- How much gravel do I need?
- Measure your area, set your desired depth, and use the calculator to estimate how much gravel you need in cubic yards. For a quick manual check: length × width × depth (in feet) ÷ 27 gives you cubic yards. Multiply by gravel density to determine how many tons you need.
- How many cubic yards in a ton of gravel?
- It depends on gravel density. Crushed stone averages around 1.4 tons per cubic yard; pea gravel runs closer to 1.3 tons per cubic yard; lighter materials like lava rock sit below 1 ton per cubic yard. The calculator adjusts automatically when you select a gravel type.
- Should I account for compaction?
- Yes — add 5–10% for standard landscape gravel and 10–15% for driveways and structural fills using crushed stone or bank run aggregate. Compaction reduces the volume of gravel after it settles, so ordering the exact calculated amount often leaves you short.
- What is the difference between pea gravel and crushed stone?
- Pea gravel is rounded, smooth, and decorative — ideal for walkways and garden beds but it does not lock together. Crushed stone consists of angular rock fragments that interlock under load, making it the better choice for driveways and any application requiring a solid foundation.
- Is there a free gravel calculator I can use?
- Yes — this free gravel calculator above handles rectangular, circular, and irregular areas. It includes cubic yard and tonne outputs, density presets for common gravel types, an inch calculator helper for depth input, and an optional price per cubic yard cost estimate.
- Can the gravel calculator estimate cost?
- Yes. Enter your price per cubic yard or price per tonne and the tool calculates the total material cost. Factor in delivery fees separately — most suppliers charge by distance and minimum load, which can add significantly to the final price.
Calculate gravel for your next project
Whether you need to estimate how much gravel or aggregate you need for a driveway, fill with gravel for a landscape bed, or calculate the amount of gravel required for a construction project, this tool removes the guesswork. Enter your dimensions, select your gravel material, and use the calculator to get an accurate cubic yard and tonne estimate — so you can order the right amount and avoid expensive over-delivery or a second trip to the supplier.