Gravel & rock
Estimate river rock volume for beds, borders, drainage and water features. See equivalent units and every active assumption.
Enter project dimensions.
Calculated quantities for your project.
Enter measurements and calculate to see the result.
Direct answer
Calculate the space a loose river-rock layer will occupy. The result is a volume based on geometry; it does not assume a universal density for rounded rock.
Use distinct calculations for dry creek beds, decorative borders, drainage landscapes and areas around water features where geometry and required depth are known.
Map changes in width along a dry creek or border as separate sections. Exclude exposed liners, large boulders and permanent features if river rock will not occupy that volume.
Rounded river rock and angular crushed rock can settle and interlock differently. Appearance names do not establish technical grading.
A dry-creek section is approximated as a trapezoid using two rectangles: 4.0 m × 1.4 m and 3.0 m × 0.8 m. Combined area is 8.0 m². At 90 mm, or 0.09 m, volume is 0.72 m³.
The example uses geometry only. It does not insert a density, package size, recommended depth or supplier tolerance.
River rock may be described by nominal size, colour and source. Confirm which attributes identify the exact quotation and obtain its loose bulk density only if mass conversion is required.
The calculator cannot design water flow, drainage, lining or structural restraint and does not infer void fill around large feature stones.
No. It only calculates entered volume; hydraulic and drainage design require appropriate expertise.
Deduct substantial objects when they materially reduce the space available to loose rock.
Review BulkMeasure’s calculation methodology, learn how to measure an area, and read about volume, density and estimated weight. Browse the calculator directory when another material or project better matches the job.