The numbers behind every calculator — densities, yields, sizes, coverage and conversions, on one page.
Free to print and pin up — every figure links to the calculator that uses it.
Conversions / 01
Unit conversions
Volume, area & weight
1 cubic yard
27 ft³
1 square yard
9 ft²
1 ton
2,000 lb
1 acre
43,560 ft²
1 cubic yard
0.765 m³
Liquid & water
1 US gallon
231 in³
1 cubic foot
7.48 gal
1 gallon of water
8.34 lb
Water
62.4 lb/ft³
1 US gallon
3.785 L
Concrete / 02
Concrete bag yields & mix
A cubic yard is 27 ft³; divide by the bag yield for bags per yard. Full breakdown on the
bag yield chart.
Bag yield & bags per yard
Bag
Yield
Per yd³
40 lb
0.300 ft³
90
50 lb
0.375 ft³
72
60 lb
0.450 ft³
60
80 lb
0.600 ft³
45
90 lb
0.675 ft³
40
Concrete facts
Density
150 lb/ft³
Weight per yard
4,050 lb
80 lb bag yield
0.60 ft³
80 lb bags / yard
45
Ready-mix ordered in
¼ yd³ steps
Aggregates / 03
Material densities (tons per cubic yard)
Loose, as-sold weights — damp or compacted runs higher. Tons on the
tonnage calculator, or each material’s own page.
Approximate t/yd³
Material
t/yd³
Material
t/yd³
Crushed stone
1.4
Road base (comp.)
1.5
#57 / river rock
1.35
Crushed concrete
1.35
Limestone
1.35
Fill dirt
1.1
Pea gravel
1.3
Topsoil
1.0
Sand (dry)
1.35
Compost
0.5
Asphalt (hot-mix)
1.95
Mulch
0.4
One yard covers 108 ft² at 3 in, 81 ft² at 4 in, 54 ft² at 6 in (27 ft³ ÷ depth).
Lumber / 04
Lumber sizes & board feet
Nominal names, actual dressed sizes — the full set on the
lumber size chart.
Nominal vs actual (in)
2 × 4
1½ × 3½
2 × 6
1½ × 5½
2 × 8
1½ × 7¼
2 × 10
1½ × 9¼
2 × 12
1½ × 11¼
4 × 4
3½ × 3½
Framing facts
Board foot
T×W(in)×L(ft) ÷ 12
Precut stud, 8 ft wall
92⅝ in
Precut stud, 9 ft wall
104⅝ in
Sheathing sheet
4 × 8 ft = 32 ft²
Rebar #4 weight
0.668 lb/ft
Coverage & waste / 05
Coverage rates & waste factors
Coverage rates
Paint
350 ft²/gal
Thinset (¼ in notch)
~80 ft²/50 lb
Drywall mud
~1 gal/100 ft²
Shingles
3 bundles/square
Brick
6.75 / ft²
Block (CMU)
1.125 / ft²
Sod pallet
~450 ft²
Typical waste
Concrete / aggregate
10%
Tile — straight / diagonal
10% / 15%
Flooring & carpet
10%
Roofing — gable / hip
10% / 15%
Drywall & siding
10%
Sod
5–10%
Quick answers / 06
Estimating FAQ
How many bags of concrete are in a cubic yard?
Forty-five 80 lb bags make a cubic yard (27 ft³ ÷ 0.60 ft³ per bag). A 60 lb bag takes 60 to the yard and a 40 lb bag takes 90. The full bag-yield chart breaks down every size.
What is the actual size of a 2x4?
A 2×4 is actually 1½ × 3½ inches once dried and surfaced. Every nominal lumber size is smaller than its name — a 2×8 is 1½ × 7¼, a 4×4 is 3½ × 3½. The lumber size chart lists them all.
How many square feet are in a cubic yard of gravel?
A cubic yard covers about 108 ft² at 3 in deep, 81 ft² at 4 in, or 54 ft² at 6 in — area = 27 ft³ ÷ the depth in feet. Weight depends on the stone: about 1.4 tons per yard for crushed stone, 1.35 for #57.
What is the standard waste factor for materials?
Roughly 10% for concrete, flooring, carpet, drywall and siding; 10% straight or 15% diagonal for tile; 10–15% for roofing by roof shape; 5–10% for sod. Waste covers cuts, breakage and the partial last unit.
How much does a cubic yard of concrete weigh?
About 4,050 lb — concrete is 150 lb/ft³ and a yard is 27 ft³. That is roughly 2.02 tons, which is why ready-mix comes on a heavy truck and bagged mix adds up fast.
Sources / 07
Sources and standards
Concrete: published Quikrete/Sakrete bag yields; 150 lb/ft³ normal-weight; 27 ft³ per yard.
Lumber: American Softwood Lumber Standard (PS 20) dressed sizes.
Aggregate densities: typical loose weights used across TrowlCalc’s material calculators — confirm with your quarry ticket.
Coverage & waste: common trade figures; every one is the value the linked calculator computes.
By the TrowlCalc teamEvery figure matches the calculator that uses it — local stock & specs governUpdated