Gravel Calculator
Estimate gravel volume and approximate tonnes from the area, depth and bulk density.
Set your values
Adjust the values, then calculate your result.
How to use Gravel Calculator
- Enter the measurements or amounts in the fields above.
- Check that dimensions, rates and units match the labels.
- Select “Estimate gravel” to see a clear estimate and the formula used.
How the gravel calculator works
Volume = area × depth in metres. Approximate mass = volume × the bulk density you enter.
Check your measurements and assumptions
Gravel density varies with rock type, grading, moisture and compaction. Ask your supplier for the product density and how it is sold before ordering by weight.
Review the estimate before you act
Compare this result with an independent measurement, supplier quote or institution guidance when the decision matters. Confirm that the units and assumptions match the labels above, and update the inputs when the conditions change. Keep a note of the values used so you can reproduce the estimate later. This calculator is a planning aid and does not replace professional, product-specific or local guidance.
How much gravel covers 20 square metres?
Multiply the area by the intended depth in metres to get cubic metres, then multiply by the supplier’s density for an approximate weight.
Is input uploaded?
Processing takes place in your browser. This tool does not send your input or selected files to a conversion API.