What is a Gravel Calculator?
A gravel calculator helps you estimate the volume and weight of gravel needed to cover a given area at a specific depth. Gravel is sold by the cubic yard or by the ton, and knowing both measurements helps you order the correct amount from suppliers and plan for delivery logistics.
Ordering too little gravel means a second delivery charge and project delays. Ordering too much wastes money and leaves you with excess material to dispose of. This calculator accounts for the type of gravel, which affects the weight-to-volume ratio due to varying densities and void spaces between particles.
Gravel Formula
Gravel Types & Weights
| Gravel Type | Weight (tons/yd³) | Size Range | Best For |
|---|---|---|---|
| Crushed Stone (#57) | 1.40 | 3/4" to 1" | Driveways, drainage |
| Pea Gravel | 1.35 | 1/4" to 1/2" | Walkways, patios |
| Crushed Limestone | 1.50 | Varies | Base material, paths |
| River Rock | 1.30 | 1" to 3" | Landscaping, dry beds |
| Lava Rock | 1.25 | 3/4" to 2" | Decorative, mulch beds |
Recommended Depths
- Driveways: 4 to 6 inches of gravel over a compacted base layer.
- Walkways: 2 to 3 inches is sufficient for foot traffic.
- Landscaping: 2 to 4 inches for decorative ground cover.
- Drainage: 6 to 12 inches for French drains and drainage trenches.
- Road base: 6 to 8 inches of compacted crusher run.
Worked Example
A walkway 20 ft long, 10 ft wide, with 4 inches of crushed stone:
Frequently Asked Questions
How many tons are in a cubic yard of gravel?
It depends on the gravel type, but most gravel weighs between 1.3 and 1.5 tons per cubic yard. Crushed stone averages about 1.4 tons per cubic yard, while denser materials like limestone can reach 1.5 tons.
How much gravel do I need for a 10x10 area?
At 4 inches deep: 100 sq ft × (4/12) ft = 33.3 ft³ = 1.23 cubic yards, or about 1.73 tons of crushed stone.
Should I order extra gravel?
Yes, order 10% extra to account for settling, compaction, and minor variations in the subgrade. Gravel compacts by approximately 10-15% after being spread and compacted.
What is the cheapest gravel option?
Crushed stone and crusher run (a mix of stone dust and small crushed rock) are typically the cheapest options, ranging from $15-30 per ton. Decorative gravels like pea gravel and river rock cost more, typically $25-50 per ton.