Simple measurements. Open calculations.

Every result starts with the dimensions and assumptions you enter. Each calculator shows its formula and a worked example so you can check the estimate before ordering.

Areas, volumes and weight

A rectangle uses length × width; a circle uses π × (diameter ÷ 2)². Additional measured sections are added and excluded areas are subtracted. Cubic yards equal square feet × depth in inches ÷ 324. One cubic foot is exactly 0.028316846592 cubic meters.

Weight is shown only when you supply a bulk density. A US short ton is 2,000 lb; a metric tonne is 1,000 kg. Moisture, grading and material state can change density, so no universal soil or stone density is assumed.

Allowances, packages and costs

An allowance multiplies the base amount by (1 + percentage ÷ 100). It is a purchasing margin, not a tested compaction model. Whole pieces and packages round up. Measured quantities retain full precision internally and are rounded for display.

Bag cost uses complete bags. Bulk cost uses the unrounded estimated volume plus the delivery charge you enter. Enter 0 when delivery is included; a blank delivery field leaves the total unavailable. The dollar sign is a display convention and no currency conversion occurs. Tax, minimum loads, bag delivery and labor are excluded.

Grass seed, drywall and paint

Seed weight uses net lawn area and the label application rate. US mode accepts lb per 1,000 sq ft; metric mode accepts g per m² and returns kg. Drywall uses the net room surface divided by sheet coverage. Paint additionally includes coat count and the product’s coverage per coat, then rounds up by can size. US paint volumes are US gallons.

Masonry, pavers and retaining walls

Bricks, blocks, tiles and pavers use area divided by the repeating unit-and-joint module. These are area estimates rather than cut-layout optimizations. Retaining wall blocks round up by units along the wall and by exposed courses, then add the specified buried courses. Caps are counted separately.

Concrete, roofing, reinforcement and fences

Concrete supports rectangular, round and hollow-cylinder pours with repeated quantities. Dry-mix bags use labeled mixed yield. Roofing expands a rectangular footprint by overhangs and a single pitch factor; one roofing square is 100 sq ft. Complex roofs need separate measured planes.

Rebar counts an orthogonal grid at the specified maximum spacing, deducts edge cover and includes the entered splice overlap. Stock is counted per run without reusing offcuts. A fence uses one straight line with an optional gate. Gate openings split the solid fence runs and are excluded from pickets and rails, while posts at the gate ends are retained.

Wood quantities and cutting

A board foot is 144 cubic inches. Doyle log yield uses (diameter − 4)² × length ÷ 16, with diameter in inches and length in feet; diameters at or below 4 inches return zero. The continuous Scribner estimate uses (0.79 × diameter² − 2 × diameter − 4) × length ÷ 16, bounded at zero. These log estimates do not reproduce every rounded scaling table or deduct defects.

Lumber cutting uses one repeated finished length, a conservative saw kerf per piece and trim at both stock ends. Decking counts rows and stock lengths without reusing offcuts between rows. Flooring divides the area with allowance by the coverage printed on a box.

What an estimate cannot decide

Sample depths, spacings, cover, rates and allowances are examples. The tools do not determine structural adequacy, retaining-wall stability, reinforcement design, roof design or playground impact protection. Follow the relevant product instructions and project specifications. The result helps build a material list; it does not inspect your site.