Cubic Yard Calculator
Calculate required bulk volume in cubic yards (yd³) for concrete, topsoil, mulch, sand, and gravel. Estimate material tonnage and retail bag counts.
| Net Surface Area | 300.0 Sq Ft |
| Net Volume (before buffer) | 2.78 Cu Yds (75.0 Cu Ft) |
| 2-Cu-Ft Bags (Mulch/Soil) | 42 Bags (2.0 cu ft each) |
| 80-lb Concrete Bags | 138 Bags (if buying bagged concrete) |
What is a Cubic Yard (cu yd / yd³)?
A Cubic Yard is the standard unit of volumetric measurement used in construction, landscaping, civil engineering, and ready-mix concrete delivery across North America.
One cubic yard represents a 3-dimensional cube that measures 3 feet wide by 3 feet long by 3 feet high. It contains exactly 27 cubic feet or 46,656 cubic inches.
The Mathematics of Cubic Yardage
Here is the proven contractor formula used to calculate cubic yards from length, width, and thickness:
Cubic Yards = (Length in feet * Width in feet * Depth in inches) / 324
Proof:
Area (sq ft) = Length (ft) * Width (ft)
Depth in Feet = Depth in inches / 12
Cubic Feet = Area * (Depth / 12)
Cubic Yards = Cubic Feet / 27 = (Area * Depth) / (12 * 27) = (Length * Width * Depth) / 324
For Circular Areas: Cubic Yards = (3.14159 * (Diameter / 2)^2 * Depth in) / 324
Total Weight (lbs) = Total Cubic Yards * Material Density (lbs/yd³)
Total Tons = Total Weight (lbs) / 2,000
Step-by-Step Worked Calculation Example
Suppose you are installing a 20 foot by 15 foot garden mulch bed at a depth of 3 inches with a 10% waste buffer:
- Calculate square footage:
20 ft * 15 ft = 300 sq ft. - Apply the 324 formula:
(300 sq ft * 3 inches) / 324 = 2.778 cubic yards net. - Add 10% waste buffer:
2.778 * 1.10 = 3.056 → 3.06 Cubic Yards. - Convert to total 2-cu-ft retail bags:
(3.056 yd³ * 27 ft³/yd³) / 2 ft³/bag = 41.25 → 42 Bags. - Calculate estimated weight (mulch at 800 lbs/yd³):
3.056 * 800 = 2,445 lbs (1.22 Tons).
Master Bulk Material Density & Weight Reference Table
Standard bulk densities, tonnages, and coverage per cubic yard:
| Material Type | Weight per Cubic Yard | Tons per Cubic Yard | Square Foot Coverage at 3" Depth | Square Foot Coverage at 4" Depth |
|---|---|---|---|---|
| Shredded Bark Mulch | 800 lbs / yd³ | 0.40 tons | 108 sq ft | 81 sq ft |
| Screened Topsoil | 2,200 lbs / yd³ | 1.10 tons | 108 sq ft | 81 sq ft |
| Coarse Mason Sand | 2,700 lbs / yd³ | 1.35 tons | 108 sq ft | 81 sq ft |
| Crushed Gravel / 57 Stone | 2,800 lbs / yd³ | 1.40 tons | 108 sq ft | 81 sq ft |
| Ready-Mix Wet Concrete | 4,050 lbs / yd³ | 2.03 tons | 108 sq ft | 81 sq ft |
| Asphalt (Compacted) | 3,915 lbs / yd³ | 1.96 tons | 108 sq ft | 81 sq ft |
Bulk Delivery vs Bagged Retail: When to Order a Ready-Mix Truck
- Under 1 Cubic Yard (< 45 bags): Buying 80-lb bags at a home improvement store and mixing in a wheelbarrow or rented electric mixer is cost-effective.
- Over 1 to 2 Cubic Yards: Hand mixing 60 to 90 bags becomes physically exhausting and risks cold joints. Ordering a ready-mix truck or bulk quarry dump delivery is strongly recommended.
- Short-Load Fees: Concrete dispatch plants usually charge a "short-load fee" for deliveries under 4 or 5 cubic yards. Always verify minimum batch delivery terms.
5 Essential Tips When Ordering Bulk Materials
Frequently Asked Questions
Multiply length in feet by width in feet by depth in inches, and divide by 324. Formula: Cubic Yards = (Length ft * Width ft * Depth in) / 324.
One cubic yard covers exactly 324 square feet at 1 inch deep, 108 square feet at 3 inches deep, and 81 square feet at 4 inches deep.
A standard contractor wheelbarrow holds 3 cubic feet. It takes approximately 9 full wheelbarrow loads to move one cubic yard of material (27 / 3 = 9).
In volume, yes (a 6-foot truck bed holds 1.5 to 2.0 cubic yards). However, pay attention to weight: 1 yard of gravel or topsoil weighs 2,200 to 2,800 lbs, which will overload half-ton (F-150 / 1500) pickup truck suspension payload capacities.
Both take up the exact same 27 cubic feet of volume. However, mulch is light (approx 800 lbs/yd³), while dense damp topsoil is nearly three times heavier (approx 2,200 lbs/yd³).