Box / room
Also: rectangular prism, bed, trench, room
V = L × W × H
L = length, W = width, H = height or depth.
Example: A parking area 30 × 10 ft, 4 in of #57 limestone: 30 × 10 × 0.333 = 100 cu ft = 3.7 cu yd, about 4.85 tons.
Quick answer: tons of #57 limestone = length × width (ft) × depth (in) ÷ 12 × 97 ÷ 2,000. A cubic yard is about 1.3 tons, and a ton covers about 82 sq ft at 3 in deep.
How to calculate how much limestone you need
- Measure the length and width in feet and choose the depth in inches.
- Cubic feet = length × width × (depth ÷ 12).
- Tons = cubic feet × weight per cu ft ÷ 2,000 (97 lb for #57, about 107 lb for loose base).
- Add allowances: about 5% for waste, plus compaction for base and screenings.
Tons = L (ft) × W (ft) × depth (in) ÷ 12 × density (lb/ft³) ÷ 2,000
A 30 × 10 ft parking area, 4 in of #57 limestone:
30 × 10 × 4 ÷ 12 = 100 cu ft. 100 × 97 ÷ 2,000 = 4.85 tons; with 5% extra, 5.1 tons.
Crushed limestone grades
| Grade | Size | Drains? | Common uses |
|---|---|---|---|
| #3 | 2–1 in | Yes | Driveway base on soft ground, drainage |
| #57 | 1 in to about 3/16 in | Yes | Drainage, driveway top, under slabs and pavers |
| #8 | ⅜ in to about 3/32 in | Yes | Paver bedding, pipe bedding |
| Dense-graded base (crusher run) | About ¾–1½ in down to dust | Poorly | Compacted base for driveways, patios and sheds |
| Screenings (#10) | About 3/16 in to dust | Poorly | Leveling, paths, paver bedding |
Numbered sizes follow ASTM D448 / AASHTO M 43. Dense-graded base has local names, such as 21A in Virginia or CA-6 in Illinois. Ask your quarry for the product that meets your job.
How much a yard of limestone weighs
| Limestone (loose) | lb per cu ft | Tons per cu yd | Basis |
|---|---|---|---|
| #57 | 97 | 1.31 | Tennessee DOT: 2,619 lb per cu yd |
| Dense-graded base | 107 | 1.45 | Tennessee DOT: 2,900 lb per cu yd loose (2.03 tons per cu yd compacted) |
| Screenings | 109 | 1.47 | Estimate: specific gravity 2.68 with about 35% air space |
Source for the Tennessee DOT figures: Roadway Design Guidelines, Chapter 4. Ask your quarry for their scale weight if you buy by the ton, and enter it as a custom density.
How far a ton of #57 limestone goes
| Depth | 1 ton covers |
|---|---|
| 2 in | 124 sq ft |
| 3 in | 82 sq ft |
| 4 in | 62 sq ft |
| 6 in | 41 sq ft |
Limestone for different shapes
Area × depth
Also: square feet to cubic feet
V = A × d
A = area, d = depth or thickness.
Example: A 400 sq ft path network, 3 in deep: 400 × 0.25 = 100 cu ft, about 4.85 tons of #57.
Sloped slab
Also: ramp, uneven depth, tapered bed
V = L × W × (h₁ + h₂) ÷ 2
L = length, W = width, h₁ and h₂ = depth at each end.
Example: Building up a driveway 50 × 12 ft from 6 in at one end to 4 in at the other with limestone base: 50 × 12 × (0.5 + 0.333) ÷ 2 = 250 cu ft, about 13.4 tons.
Trench / trapezoid
Also: ditch, berm, swale, trapezoidal prism
V = (a + b) ÷ 2 × h × L
a = top width, b = bottom width, h = depth, L = length.
Example: A drain trench 12 in wide, 18 in deep and 40 ft long: 60 cu ft, about 2.9 tons of clean #57.
Cylinder
Also: round hole, post hole, tank, planter
V = π × r² × h
r = radius (half the diameter), h = height.
Example: A round patio base 10 ft across, 4 in deep: π × 5² × 0.333 = 26.2 cu ft, about 1.27 tons.
Worked examples
Paver patio base
A 12 × 12 ft patio: 4 in of dense-graded base with a 15% compaction allowance is 48 × 1.15 = 55.2 cu ft, × 107 ÷ 2,000 = 2.95 tons. Add 1 in of screenings for bedding: 12 cu ft, × 109 ÷ 2,000 = 0.65 tons.
- Other stone? Use the stone calculator or the gravel calculator.
Frequently asked questions
How much crushed limestone do I need?
Multiply length × width in feet by the depth in inches ÷ 12 to get cubic feet. Multiply by the weight (about 97 lb per cu ft for loose #57 limestone) and divide by 2,000 for tons. A 30 × 10 ft area 4 in deep is 100 cu ft, or about 4.85 tons.
How many tons of limestone are in a cubic yard?
Loose #57 limestone is about 1.3 tons per cubic yard (the Tennessee DOT uses 2,619 lb for estimating). Dense-graded limestone base is about 1.45 tons loose and closer to 2 tons once compacted in place.
How much does a ton of limestone cover?
A ton of #57 limestone is about 20.6 cu ft: roughly 124 sq ft at 2 in deep, 82 sq ft at 3 in and 62 sq ft at 4 in.
What is the difference between #57 limestone and limestone screenings?
#57 is clean stone from 1 in down to about 3/16 in, with no fines, so water drains through it. Screenings (#10) are the fine material left from crushing, from about 3/16 in down to dust. They pack firm and are used for leveling and under pavers, but they drain poorly.
What limestone is best for a driveway?
A compacted base of dense-graded limestone (often sold as crusher run, ¾ in minus or by a local name such as 21A or CA-6), often topped with #57 or more base. Clean #57 alone stays loose on top and can rut.
Why add a compaction allowance?
Dense-graded base and screenings pack down a lot under a plate compactor or roller. Choose an allowance so you order enough loose stone for the finished depth. Clean #57 settles much less.
Does limestone raise soil pH?
Crushed limestone is calcium carbonate, the same mineral as agricultural lime, so runoff and fines from it can raise the pH of the soil next to it a little. Keep acid-loving plants such as azaleas and blueberries away from limestone paths.
Is this limestone calculator free to use online?
Yes. The CalcWall Limestone Calculator is completely free and works online in any browser, on a phone, tablet or computer. There is nothing to download and no account to create, and the math runs right in your browser, so results appear as you type.