Why use a Gravel Calculator?
Ordering too little gravel can stall your project, while ordering too much ties up your budget and space. The Gravel Calculator solves this by translating simple inputs—shape, dimensions, depth, and material density—into clear, actionable quantities. Whether you are covering a rectangular driveway or a circular seating area, you will get precise estimates in cubic meters, cubic yards, metric tonnes, and US tons. You can also include a waste factor to account for compaction, grading, and spillage, so the delivered amount matches real-world installation needs.
How to use the Gravel Calculator
- Select your project shape: Rectangle for length × width, or Circle for diameter.
- Enter dimensions using your preferred length unit: feet or meters.
- Enter the compacted gravel depth in inches or centimeters.
- Set the bulk density (kg/m³). If you are unsure, 1600 kg/m³ is a common default for many gravels.
- Add a waste/compaction percentage (typically 5–10%).
- Optionally, enter a bag size to estimate the number of pre-packed bags.
- Optionally, enter your price and select the matching unit to get a total cost estimate.
Typical depths and densities
Depth depends on the application and base preparation:
- Garden paths and decorative areas: 2–4 in (5–10 cm)
- Patios and walkways with traffic: 3–4 in (7.5–10 cm)
- Driveways and parking: 4–6 in (10–15 cm), often layered
Bulk density varies with stone type, size, and moisture content. Many gravels fall between 1500–1700 kg/m³. Angular, well-graded blends may compact more tightly, increasing effective density, while rounded pea gravel may sit looser. For best results, confirm the density with your supplier, especially for specialty aggregates.
What the Gravel Calculator returns
Once you submit your inputs, the Gravel Calculator computes:
- Adjusted volume including waste: in cubic meters and cubic yards
- Estimated weight: in metric tonnes and US tons
- Optional bag count based on your chosen bag size (kg)
- Optional total material cost using the pricing unit you select
Behind the numbers
The calculator finds area from your shape selection. For rectangles, it multiplies length by width. For circles, it uses the diameter to determine the radius and computes area with the standard circle formula. It then converts your depth to meters, multiplies by area to get volume, and applies the waste factor. Using the bulk density, it estimates total weight and converts to both metric tonnes and US tons. Unit conversions ensure that no matter how you enter your measurements, you get consistent results.
Pro tips for accurate ordering
- Measure twice, and round up dimensions to the nearest 0.5 ft or 0.1 m for a buffer.
- Account for edging, slopes, and any graded transitions that increase depth locally.
- Use a slightly higher waste factor (8–10%) for irregular areas or DIY projects.
- Ask your supplier about moisture content and density to refine the estimate.
- If you need a specific finished thickness, compact in layers rather than dumping all at once.
When to order by weight vs. volume
Suppliers may price gravel by tonnage or by cubic yard/meter. If your supplier prices by weight, use the weight results to align your order. If they sell by volume, rely on the cubic yards/meters the Gravel Calculator provides. For bagged products, the bag count ties directly to the weight estimate and makes small projects easy to plan and stage.
Make your project smoother
The Gravel Calculator removes guesswork so you can focus on design, scheduling, and execution. Combine accurate quantities with proper site preparation—graded base, geotextile fabric if needed, and thoughtful edging—to get a clean, durable surface that drains well and looks great for years.
