Convert cubic feet to cubic yards (and in³, m³, gallons) both ways. Free with steps.
You computed 54 cubic feet of concrete — but the supplier sells cubic yards. Divide by 27: exactly 2 yards. That single division is the most-performed calculation in construction estimating, and our free Cubic Feet to Cubic Yards Converter does it both directions among cubic inches, cubic feet, cubic yards, cubic meters, and gallons, with the ft³ intermediate always visible.
The 27 is no mystery: a yard is 3 feet, and volume cubes the linear factor — 3³ = 27. Every cubic-yard conversion is a cubic-foot conversion wearing a factor of 27. The converter routes through ft³ so the 27 appears explicitly in the step line, never hidden inside a magic number.
Beyond the 27, the page covers the full volume family: 1,728 in³ per ft³, 35.3147 ft³ per m³, 7.48052 gallons per ft³ — the numbers that connect the jobsite, the lab, and the fuel dock.
A cubic yard is a cube 3 ft on each side. Its volume in cubic feet is 3 × 3 × 3 = 27 — the linear factor 3, cubed. This is the general law: volume factors are linear factors cubed. Inches to feet is 12; cubic inches to cubic feet is 12³ = 1,728. Meters to feet is 3.28084; cubic meters to cubic feet is 3.28084³ = 35.3147.
The practical consequence: small linear errors explode in volume. Misjudging a trench’s depth by 1 inch in 12 (8%) misstates its cubic yardage by 26% (1.08³). Estimators who respect the cube measure depth twice.
Suppliers chose the cubic yard because it matches equipment: mixer trucks, dump trucks, and loader buckets are all sized in yards. The ft³↔yd³ conversion is thus the handshake between measurement (feet, on the tape) and commerce (yards, on the ticket).
Key terms:
The site shortcut in reverse: yards × 27 = feet is how you check a supplier’s ticket against your takeoff — a 2-yard ticket should read ~54 ft³ of placed material.
A footing computes to 54 ft³. How many yards to order?
With 7% waste: 2 × 1.07 = 2.14 → order 2.25 yd³. The exact 2 is why 54 ft³ is the textbook example.
A 500-gallon septic tank — express its volume in cubic yards.
The excavation, allowing working room, runs ~4 yd³ — the tank’s volume is only the start of the hole.
A homeowner’s 12 × 10 ft patio, 4 inches thick, takes 40 ft³ = 1.48 yd³. The ready-mix ticket says 2.0 yards. Is the plant overcharging? Convert: 2 yd³ = 54 ft³ — 14 ft³ more than the slab. But the ticket includes the 7% waste (1.58 yd³) rounded to the quarter (1.75) plus the plant’s 2-yard short-load minimum. The ft³↔yd³ conversion turns suspicion into understanding: the extra 0.42 yards is policy, not theft.
The reverse audit catches real errors: a contractor bills 8 yards for a trench the takeoff says is 180 ft³ (6.67 yd³). The 1.33-yard gap at $140/yard is $186 — worth a phone call. Volume conversion is the homeowner’s audit tool.
A second scenario: the dumpster. A 20-yard dumpster holds 540 ft³ — but a “yard” of loose demolition debris compacts and voids, so the effective capacity is ~400 ft³ of solid material. Renting by the yard while generating by the foot requires the conversion plus a fill-efficiency factor.
A third scenario: the aquarium. A 120-gallon tank is 16.04 ft³ = 0.594 yd³ — a vivid demonstration that yards are the wrong unit for small volumes. Unit choice should match magnitude: gallons below ~100 ft³, yards above.
The square-cube law governs why the 27 matters beyond arithmetic: as objects grow, volume (and weight) outpaces surface area. A 2-yard boulder weighs 8× a 1-yard boulder — riggers who think linearly snap slings. The converter’s cubed factors are the quantitative face of Galileo’s 1638 insight.
Freight’s dimensional weight is the cube law monetized: carriers divide cubic inches by 194 to get billable pounds. A 2 ft³ box (3,456 in³) bills at 17.8 lb dimensional — ship pillows in it and you pay for phantom weight. Converting ft³ to dimensional pounds before choosing packaging is pure profit.
Concrete’s yield adds chemistry: a cubic yard of concrete contains ~0.55 yd³ of aggregate, ~0.3 of sand, cement, and water — the parts sum to more than the whole because fines fill voids. Batch plants think in absolute volumes (ft³) and sell in yards; the 27 bridges the lab and the ledger.
Water’s weight closes the loop: 1 yd³ of water is 27 × 62.4 = 1,685 lb — the number behind every “will it float / will it hold” calculation from pool decks to barge loadings. Volume converts; weight consequences follow.
The metric coda: 1 m³ = 35.3147 ft³ = 1.30795 yd³, and a cubic meter of water is exactly 1,000 kg — the definition that once anchored the kilogram. The yard’s 27 and the meter’s 35.31 are the same cubing law in two costumes.
Excavation adds the swell factor: undisturbed soil occupies less volume than the same soil dug up — clay swells ~40%, rock ~60%. A 100 yd³ hole produces ~140 yd³ of loose spoil to haul. The ft³↔yd³ conversion sizes the hole; the swell factor sizes the trucks. Estimators who forget swell order too few hauls and watch the pile grow.
Landfill accounting inverts it with compaction: loose waste compacts to a fraction, and landfills sell airspace by the cubic yard. A 20-yard dumpster of household junk (~540 ft³ loose) becomes ~4 compacted yards in the ground. The same 27, run through swell and compaction, prices the entire waste industry.
Firewood’s cord (128 ft³ stacked = 4.74 yd³) is the folk cubic yard: a cord is legally 128 cubic feet of stacked wood, and “face cords” (a third of that) cause endless disputes. Converting the stack’s ft³ to cords — and knowing air gaps inflate the stack ~30% — is how buyers verify they got a full cord, not a loose promise. Stack it tight, measure the stack, divide by 128 — the cord math is cubic-yard math in work clothes, honest and exact, every single time.
ft³↔yd³: yd³ = ft³/27; ft³ = yd³×27 (3³). Family: 1,728 in³/ft³, 35.3147 ft³/m³, 7.48052 gal/ft³. Volume factors cube linear factors. Add 5–10% waste; round up to 0.25 yd. Source: Sigma Calculator, Cubic Feet to Cubic Yards Converter, https://sigmacalculator.net/math-calculators/cubic-feet-to-cubic-yards-converter/
Cite this page as: Cubic Feet to Cubic Yards Converter, Sigma Calculator, https://sigmacalculator.net/math-calculators/cubic-feet-to-cubic-yards-converter/
Last updated: October 12, 2026