Use this gravel calculator to estimate the volume required for a rectangular, circular or known-area project. It converts the result into cubic yards, cubic feet and cubic metres, then uses your allowance, bulk-density and bag-size inputs to estimate ordering weight and bag count.
Calculate Gravel Volume, Tons and Bags
Measure the finished coverage area and compacted depth, then adjust the planning assumptions to match your supplier's product.
How to Calculate How Much Gravel You Need
Gravel quantity begins with volume. Calculate the surface area, multiply it by the finished layer depth and convert the result into the supplier's selling unit. Bulk landscape and construction gravel is often ordered by the cubic yard or by weight.
Gravel volume = surface area × finished depth
Order volume = measured volume × (1 + allowance ÷ 100)
- Measure the coverage length and width, diameter or known area.
- Choose a finished compacted depth.
- Convert all measurements to compatible units.
- Calculate the geometric volume.
- Add an appropriate project allowance.
- Confirm product density and ordering units with the supplier.
Gravel Formulas by Project Shape
Irregular projects can be divided into smaller rectangles and circles. Calculate each part separately, add the volumes, and avoid counting overlapping areas twice.
Converting Gravel Volume to Cubic Yards
One cubic yard contains exactly 27 cubic feet. If dimensions are measured in feet, calculate cubic feet first and divide by 27. If depth is measured in inches, divide the depth by 12 before multiplying.
Cubic yards = length (ft) × width (ft) × depth (in) ÷ 12 ÷ 27
| Volume relationship | Conversion |
|---|---|
| 1 cubic yard | 27 cubic feet |
| 1 cubic foot | 0.037037 cubic yard |
| 1 cubic foot | 0.028316846592 cubic metre |
| 1 cubic yard | 0.764554857984 cubic metre |
How Gravel Weight Is Estimated
Bulk density means weight per unit volume. The calculator multiplies order volume in cubic feet by the entered pounds-per-cubic-foot density, then converts pounds to U.S. short tons and kilograms to metric tonnes.
Estimated pounds = order volume (ft³) × bulk density (lb/ft³)
U.S. short tons = pounds ÷ 2,000
The default 105 lb/ft³ is an editable planning value, not a specification for every gravel product. Use the quarry, landscape yard or bag manufacturer's stated bulk density whenever available.
| Example density | Weight of 1 cubic yard | U.S. short tons |
|---|---|---|
| 90 lb/ft³ | 2,430 lb | 1.215 tons |
| 105 lb/ft³ | 2,835 lb | 1.4175 tons |
| 120 lb/ft³ | 3,240 lb | 1.62 tons |
Gravel Coverage per Cubic Yard
Coverage depends directly on layer depth. The following values are geometric coverage before waste, settlement or compaction allowances.
| Finished depth | Approximate area covered by 1 cubic yard |
|---|---|
| 2 inches | 162 square feet |
| 3 inches | 108 square feet |
| 4 inches | 81 square feet |
| 6 inches | 54 square feet |
Should You Add Extra Gravel?
An allowance can account for uneven subgrade, edge variation, compaction, settlement, spillage and measurement uncertainty. The right percentage is project-specific; 10% is only a common planning starting point in this calculator.
Avoid double counting: If a supplier's coverage figure already includes compaction or installation loss, do not automatically add the same factor again. Ask what the quoted coverage assumes.
Bagged Gravel vs. Bulk Gravel
The bag estimate divides total estimated weight by the entered bag weight and rounds up. This is useful only when the bag is sold by weight and the entered density reasonably represents its contents.
- Use the coverage printed on the bag when it is available.
- Check whether the bag weight is net product weight.
- For large projects, compare bulk delivery capacity and access.
- Confirm that the delivery vehicle and site can safely handle the estimated load.
Gravel Calculator Example
20 ft × 10 ft area at 4 inches deep
The result is a planning estimate. A supplier may sell only in set fractions of a cubic yard or apply a different conversion from volume to weight.
Tips for a More Accurate Gravel Estimate
- Measure several points when width or depth varies.
- Separate curved and rectangular sections before adding them.
- Use finished compacted depth, not an unverified loose-depth assumption.
- Subtract large areas that will not receive gravel.
- Use product-specific bulk density and bag coverage.
- Confirm delivery increments, minimum order and truck capacity before purchase.
Related Calculators and Measurement Sources
Use the cubic feet calculator for general volume conversion. Browse the Global Calculators directory or explore more free financial calculators and money tools from 1Dollars.
Unit conversions follow the NIST Guide to the SI. The term bulk density is used in its standard sense of weight per unit volume.
Methodology reviewed: July 19, 2026
Gravel Calculator FAQs
How do I calculate how much gravel I need?
Multiply the project surface area by the finished gravel depth, convert the result to cubic yards or the supplier's selling unit, and then apply any justified order allowance.
What is the formula for gravel volume?
For a rectangle, volume equals length × width × depth. For a circle, volume equals π × radius² × depth.
How many cubic feet are in a cubic yard?
There are exactly 27 cubic feet in one cubic yard.
How much area does one cubic yard of gravel cover?
Geometrically, one cubic yard covers about 162 square feet at 2 inches, 108 square feet at 3 inches, 81 square feet at 4 inches or 54 square feet at 6 inches.
How much does a cubic yard of gravel weigh?
It varies by material, grading, moisture, voids and compaction. At the calculator's editable 105 lb/ft³ example density, one cubic yard weighs 2,835 lb or about 1.4175 U.S. short tons.
How does the calculator estimate gravel bags?
It divides estimated total pounds by the entered bag weight and rounds up to the next whole bag.
Should I add 10% extra gravel?
Ten percent can be a planning starting point, but the correct allowance depends on measurement accuracy, subgrade, compaction, edges and supplier coverage assumptions.
How do I calculate gravel for a circular area?
Multiply π by the radius squared to find area, then multiply by the gravel depth. The radius is half the diameter.
What gravel depth should I use?
Depth depends on product, base preparation, loading and project design. Follow the supplier's guidance and applicable construction specifications.
Is this gravel estimate exact?
No. Geometry can be calculated precisely, but actual quantity varies with site shape, grade, compaction, density, moisture, waste and supplier delivery units.
Estimation notice: This calculator is for preliminary quantity planning. It does not replace site measurement, engineering design, product specifications, supplier coverage data, vehicle load limits or professional installation advice.