Construction Gravel Calculator
Enter project dimensions, compacted depth, density, waste, moisture, truck capacity, and pricing details.
Example Data Table
| Project | Area | Depth | Compaction | Waste | Estimated Gravel |
|---|---|---|---|---|---|
| Small walkway | 120 sq ft | 3 in | 10% | 5% | 1.28 cu yd |
| Patio base | 300 sq ft | 4 in | 12% | 8% | 4.48 cu yd |
| Driveway base | 720 sq ft | 6 in | 15% | 10% | 16.87 cu yd |
Formula Used
Area for rectangle: Length × Width
Area for circle: π × Radius²
Area for trapezoid: ((Width One + Width Two) ÷ 2) × Length
Compacted volume: Area × Depth
Cubic yards: Cubic feet ÷ 27
Loose gravel required: Compacted cubic yards × Grade factor × Compaction factor × Waste factor
Weight: Loose cubic yards × Density × Moisture factor
Tons: Weight in pounds ÷ 2,000
Total cost: Material cost + Delivery fee + Tax
How to Use This Calculator
Choose the shape that matches your work area. Enter length, width, second width, diameter, or known area as needed. Add the final compacted depth required for the base. Use inches for most construction base projects.
Set compaction allowance for material settlement. Add waste for edge loss, spreading variation, and ordering safety. Enter local density when your supplier provides it. Add moisture adjustment when gravel is wet or stored outside.
Choose a pricing mode. You can estimate by ton, cubic yard, or bag. Add delivery, tax, truck capacity, and bag weight. Press calculate. The result appears above the form, below the header section.
Guide to Estimating 1/4 Minus Gravel
What 1/4 Minus Gravel Means
1/4 minus gravel is a compactable aggregate mix. It contains small stone and fine particles. The largest particles are usually near one quarter inch. The fines help lock the material together. This makes it useful for paths, patios, paver bases, shed pads, and light driveway layers.
Why Depth Matters
Depth has a strong effect on material quantity. A shallow decorative layer may need only a few cubic yards. A structural base needs more material. Many projects use a compacted depth target. Loose gravel normally reduces after compaction. That is why this calculator adds a compaction allowance.
Why Compaction and Waste Are Included
Construction estimates should not use raw volume alone. Gravel can settle during spreading, grading, watering, and plate compaction. Edges may also require extra material. Some gravel can be lost during unloading. Waste allowance helps avoid short orders. It is usually better to have a small surplus than stop work before the base is complete.
Weight and Delivery Planning
Suppliers may sell 1/4 minus gravel by ton or cubic yard. Weight depends on density and moisture. Wet material can weigh more than dry material. This calculator uses density and moisture inputs to estimate dry weight, wet weight, tons, and metric tonnes. It also estimates truck loads based on your selected truck capacity.
Cost Estimating
The calculator supports price per ton, price per cubic yard, and price per bag. This helps compare bulk delivery with bagged material. Bulk gravel is often practical for larger work. Bags can suit small repairs or limited access areas. Add delivery and tax to estimate the true order cost.
Better Job Preparation
Use the geotextile area estimate when fabric is needed below the gravel. The calculator adds a simple overlap allowance. Review the chart after calculating. It shows compacted volume, loose volume, tons, and cost together. This helps contractors, homeowners, and estimators check the order before calling a supplier.
FAQs
1. What is 1/4 minus gravel used for?
It is used for compacted bases, pathways, patio foundations, shed pads, and small driveway layers. The fines help bind the gravel after compaction.
2. Why does the calculator add compaction allowance?
Loose gravel settles during spreading and compaction. The allowance helps estimate the extra material needed to reach the final compacted depth.
3. Should I order by tons or cubic yards?
Use the same unit your supplier uses. If they sell by tons, rely on the weight result. If they sell by yard, use cubic yards.
4. What density should I enter?
Use your supplier’s listed density when available. If not, use a reasonable local estimate and add waste for safety.
5. Does moisture change the estimate?
Moisture can increase total weight. This matters when pricing, hauling, or checking truck capacity. Enter a moisture percentage when material is wet.
6. Can I use this for paver base work?
Yes, it can estimate compacted gravel base quantities. Always follow local base depth and drainage requirements for your project type.
7. Why is geotextile area included?
Fabric may help separate soil from gravel. The calculator adds an overlap allowance to help estimate fabric coverage.
8. Why do results differ from supplier quotes?
Supplier quotes may use different density, moisture, truck capacity, minimum delivery, or rounding rules. Use this estimate as a planning guide.