Calculators
Garden and yard calculators
Twelve calculators that turn the measurements of a bed, a lawn, a path or a fence line into a quantity you can order.
Every one works in feet and inches or in metric, shows how the answer was worked out, and ends with a shopping list you can print. None of them asks you to sign up for anything.
Beds & soil
Mulch Calculator
Cubic yards or bags for any bed shape and depth, with a bags-versus-bulk cost check.
Raised Bed Soil Calculator
Fill volume for one bed or several, split into a soil mix recipe with settling allowed for.
Topsoil & Compost Calculator
How much to spread, top-dress or dig in, by depth or by mix percentage.
Plant Spacing Calculator
How many plants fill a bed on a square or triangular grid, or along a hedge line.
Lawn
Sod & Grass Seed Calculator
Rolls and pallets of sod, or pounds of seed by grass type, for a new lawn or overseeding.
Lawn Fertilizer Calculator
Turn the N-P-K numbers on the bag into the weight of product your lawn needs.
Paths, patios & walls
Gravel & Stone Calculator
Volume and tons for paths, drives and beds, by stone type, with compaction.
Paver Patio Calculator
Pavers by size and pattern, plus base gravel, bedding sand and edging.
Retaining Wall Block Calculator
Blocks, caps, base and drainage gravel for a garden wall, buried course included.
Concrete Calculator
Slabs, footings and post holes in bags or ready-mix, with the break-even point.
Fences & decks
Fence Calculator
Posts, rails, pickets and concrete from one run length, gates included.
Deck Calculator
Deck boards, joists and fasteners from the deck size, board width and gap.
How to use them
Measure first. Every calculator starts from a length, a width and usually a depth, and the answer can only be as good as those numbers. If your bed or lawn is an odd shape, measure it in simple pieces and add the areas together, then choose the "I know the area" option. Our guide to measuring irregular beds shows four ways to do it.
Then read the breakdown, not just the headline. Each result comes with a table showing the area, the volume, the allowance that was added, and how the total was rounded. If a figure looks wrong, the table will usually show you which measurement to check.
Finally, treat the answer as an estimate. Bag sizes, stone densities and seeding rates vary between brands and suppliers. Every page lists the values it assumed and lets you change the ones that matter. The reasoning behind those values is set out on the methodology page.
What the calculators have in common
- They round up. You cannot buy part of a bag or lay part of a block, and running short costs more than a small surplus.
- They show the allowance separately. Extra for uneven ground, settling, compaction or cutting waste is always its own line, so you can see it and change it.
- They give both ways of buying. Bags and bulk, or bags and ready-mix, with a cost comparison if you enter local prices.
- They do not design structures. Quantities for a deck, a wall or a footing are not a substitute for building code, a permit or an engineer where one is needed.