All calculators

19 calculators, grouped by the part of the job they belong to.

Concrete & Masonry

Concrete block calculator — How many concrete blocks and bags of mortar for a wall. Coverage is worked out from the real 15-5/8 in block plus your joint width, not a rule of thumb.
Concrete footing calculator — Cubic yards, bags and rebar for strip footings, pads and round deck piers. The rebar count includes code lap splices — where most estimates fall short.
Concrete calculator for post holes — How many bags of concrete per fence post, with the post itself subtracted from the hole. Works for 4x4, 6x6 and metal posts, general or fast-setting mix.
Concrete slab calculator — Work out the cubic yards, bags of concrete mix and total weight for a slab. Enter length, width and thickness, and see whether bagged mix or ready-mix is cheaper.

Grass seed calculator — How much grass seed you need, at the rate published for your grass type. Bermuda takes 2 lb per 1,000 sq ft and tall fescue 8 — one rate ruins lawns.
Gravel calculator — Work out tons and cubic yards of gravel for a driveway, shed base or path. Includes the compaction allowance and per-stone densities most calculators skip.
Mulch calculator — Work out cubic yards and bags of mulch from your bed area and depth. Includes the coverage per cubic yard at your depth — the figure most calculators omit.
Paver sand calculator — Work out bags of bedding sand and polymeric joint sand for a paver patio. Uses the ICPI 1 in bedding depth and coverage by joint width, not a flat figure.
Paver calculator — How many pavers you need, plus the crushed stone base under them — with the compaction allowance and the wider excavation most calculators leave out.
Sod calculator — Work out pallets, slabs or rolls of sod from your lawn area. Pallet coverage runs from 400 to 700 sq ft by region, so this asks for yours instead of guessing.
Topsoil calculator — Work out cubic yards and bags of topsoil for a raised bed, lawn or garden. Uses the 0.75 cu ft bag stores actually stock, and allows for settling.

Drywall calculator — Sheets of drywall for a room, plus the joint compound, paper tape and screws to finish it. Uses the manufacturer coverage tables, not the 0.05 gal/sq ft myth.
Floor tile calculator — How many floor tiles you need, rounded up to whole boxes, with the waste factor set by your layout and the thin-set bags to go with it. Diagonal and herringbone cost more.
Laminate flooring calculator — How many boxes of laminate flooring to buy, not just the square footage. Box coverage varies from 16 to 30 sq ft by style, so the count is never the same twice.
Paint calculator — How many gallons of paint a room needs. Deducts the doors and windows, and prices the first coat separately because bare drywall drinks it.
Wallpaper calculator — How many rolls of wallpaper you need, counted in strips and adjusted for the pattern repeat. A 25 in repeat on an 8 ft wall throws away a fifth of every roll.

Deck board calculator — How many deck boards you need, in the lengths you can actually buy. Uses the real 5.5 in board width and your board gap, and counts the deck screws too.
Fence picket calculator — How many fence pickets, posts and rails you need for a run of fence. Uses real dressed lumber widths — a 1x6 is 5.5 in, not 6 in — so the count is right.
Roof shingle calculator — Bundles of shingles for your roof, corrected for pitch. Also gives the starter strip and hip and ridge cap most calculators leave out, so you buy once.