A shallow rectangular layer
A 12 × 10 ft area at 3 in depth contains 30 ft³. With 10% allowance it becomes 33 ft³. Bags containing 0.5 ft³ require 66 bags.
Compare bag counts, bulk volume and mass using your supplier’s density.
Project measurements
For a circle or ring, enter the outside diameter.
Illustrative value only. Moisture, stone type and compaction change bulk density.
Use one currency throughout; tax, labor and delivery excluded.
Prices use your chosen currency consistently. Blank price skips cost. Example coverage, density, yield and prices are editable scenarios, not current product offers.
Material takeoff
Estimated purchase quantity
66 bags
Rectangular gravel layer · uniform depth
Illustration is schematic, not an installation drawing.
| Net ground area | 120 ft² |
|---|---|
| Geometric volume | 1.11 yd³ |
| Volume | 1.22 yd³ |
| Cubic feet | 33 ft³ |
| Liters | 934.46 L |
| Bulk alternative (rounded) | 1.25 yd³ |
| Estimated target mass | 1.65 US short tons |
| Bagged material cost | Not entered |
Method: Net area × depth × (1 + allowance/100); bags = ceiling(volume ÷ bag volume), mass = target volume × entered bulk density.
Enter density from your supplier for the intended moisture and compaction condition. The allowance is an added percentage, not an automatic compacted-to-loose conversion. Bulk mass excludes rounding to the supplier volume increment. This does not design a base or drainage layer.
Quantity and material-only cost estimate. Verify field measurements, product instructions and your purchase units. Labor, delivery, taxes, equipment and structural adequacy are excluded.
Calculations run in your browser. This tool does not request a location, retrieve live prices or send your measurements to a material supplier.
How to use the Gravel Calculator
- 01
Choose rectangle, circle or ring, then enter the layer footprint and exclude any unfilled patches.
- 02
Enter the depth, bag volume and added allowance. Ask your supplier for the relevant loose or compacted bulk density.
- 03
Set the supplier’s volume increment and optional price per bag. Compare the volume and target mass before ordering.
Examples
Density changes the mass
Using an illustrative density of 100 lb/ft³, 33 ft³ weighs 3,300 lb, or 1.65 US short tons. A different density changes mass but not the geometric bag count.
Density must match the material condition
Bulk density includes the spaces between stones. Rock type, grading, moisture and compaction can all change the mass per volume. A solid mineral density is not interchangeable with supplier bulk density. The example field is an editable scenario, not a material specification.
Loose and compacted volume
The allowance adds a percentage to the measured layer volume. It does not automatically convert a compacted layer to delivered loose material. Obtain a suitable conversion or allowance from the supplier. The calculator does not choose drainage design, base thickness or load capacity.
What to know
- Material quantities and user-price scenarios only; no structural adequacy, code compliance or installation approval.
- Example product values are illustrative. Verify your measurements and current product label before ordering.
Common questions
Which ton does the result use?
US mode reports short tons of 2,000 lb; metric mode reports tonnes of 1,000 kg. The displayed label identifies the unit.
Is the mass based on the rounded bulk order?
No. It uses the target volume after allowance. The bulk alternative is separately rounded to the supplier increment.
What if gravel is sold by bag weight?
Use the labeled volume or ask for its bulk yield. Weight can only be converted to volume when the relevant bulk density is known.