Gravel Calculator - How Much Gravel Do I Need?

Calculate exactly how much gravel you need for driveways, pathways, and landscaping projects. Our free gravel calculator accounts for area dimensions and depth to provide accurate volume calculations and help you purchase the right amount of gravel for your project.

How to Use the Gravel Calculator

Measure your area: Enter the length and width of the area you want to cover with gravel in feet. For irregular areas, break them into rectangular sections and calculate each separately.
Choose gravel depth: Select the recommended depth based on your project type. Driveways typically need 3-4 inches, while pathways can use 2-3 inches.
Select bag size: Choose the gravel bag size you're planning to purchase. Most gravel comes in 0.5 cubic foot bags, but check your local supplier.
Review results: The calculator shows bags needed with a 5% waste factor included.

Pro tip: Always order 10% extra gravel to account for settling and compaction. Gravel can compact significantly when driven on or walked on.

Understanding Your Gravel Calculation

Our gravel calculator uses precise volume calculations to determine exactly how much gravel you need. Understanding these calculations helps you make informed decisions about your landscaping or driveway project.

Volume Calculation

Gravel volume is calculated using the formula: Volume = Length × Width × Depth (converted to feet). This gives you the total cubic footage of gravel needed for your project area.

Gravel Depth Guidelines

Different applications require different gravel depths:

2 inches: Garden paths and decorative areas
3 inches: Driveways and parking areas
4 inches: Heavy traffic areas and base layers
6 inches: Road base and structural applications

Example: A 20×10 foot driveway with 3 inches of gravel requires approximately 45 cubic feet or 90 standard 0.5-cubic-foot bags of gravel.

Compaction Factor

Gravel settles and compacts over time, especially under traffic. The 5% waste factor accounts for this settling, but you may need additional gravel for areas that will be heavily used.

Gravel Types & Applications

Crushed Stone

• Angular pieces, excellent drainage
• Best for: Driveways, road base
• Compacts well, stable surface
• Available: #57, #67, #411 stone
• Cost: $30-50 per cubic yard

Pea Gravel

• Smooth, rounded stones
• Best for: Pathways, gardens
• Easy to walk on barefoot
• Doesn't compact as firmly
• Cost: $25-40 per cubic yard

River Rock

• Naturally rounded stones
• Best for: Decorative landscaping
• Various colors and sizes
• Poor drainage if too fine
• Cost: $40-60 per cubic yard

Gravel Installation

• Excavate 4-6 inches below grade
• Add base layer for stability
• Compact in 2-3 inch layers
• Use edging to contain gravel
• Slope for proper drainage

Gravel Installation Tips & Best Practices

Prepare the base: Excavate 4-6 inches below the final grade for proper base preparation
Add base layer: Use larger gravel or crushed stone as a base layer for stability
Compact in layers: Spread and compact gravel in 2-3 inch layers for best results
Use landscape fabric: Install fabric underneath to prevent weed growth and migration
Install edging: Use plastic or metal edging to contain the gravel and maintain shape
Provide drainage: Ensure proper slope (1/8 inch per foot) for water runoff
Allow settling: Gravel will settle 10-20% after installation - top off as needed
Regular maintenance: Add gravel annually to maintain depth and appearance