Twelve free calculators for concrete, block, brick, pavers and the materials under and around them — quantities computed from geometry and public formulas with the working shown, never from copied code tables or any brand's specs. Free, no signup, runs entirely in your browser. These are planning tools: structural work follows your plans, local code, and an engineer where required.
Start with the Concrete Calculator for the volume in yards and bags — slabs, footings, columns and steps all sum into one pour. Mixing on site instead of ordering? The Mix Ratio Calculator splits that volume into cement, sand and gravel at your ratio. The Rebar Calculator counts grid bars, footing runs or wire mesh from your plan's spacing, and the Concrete Weight Calculator tells you what the cured slab weighs — or, for demolition, what the broken-up debris weighs and how much dumpster it fills. Setting posts? The Fence Post Concrete Calculator does bags per hole directly.
The Paver Calculator ties the whole dry-laid build-up together: paver count by size and joint, base gravel by your depth, the 1″ bedding sand layer, and polymeric joint sand from joint geometry — with a cost section that runs on your local prices. Paving with hot mix instead? The Asphalt Calculator converts area and depth to tons, including the square-yards-to-tons math estimators quote in. Bulk material orders for either route go through the Sand Calculator and the Gravel Calculator.
Block walls start at the Concrete Block Calculator — blocks, mortar bags, and grout for filled cores, with core volumes computed from shell-and-web geometry. Brick veneer or solid brick walls are the Brick & Mortar Calculator's job, including repointing. Coating the finished wall? The Stucco Calculator figures scratch, brown and finish coats — render and plaster too. And a landscape wall that holds back soil is the Retaining Wall Block Calculator: blocks per course plus the base gravel trench and drainage backfill everyone under-orders.
Bulk materials that serve every project above — they live in the wider Home & DIY collection.
The Gravel Calculator converts any base, drainage or driveway stone volume to tons with density presets, and the Cubic Yards Calculator handles raw volume conversions for anything the project tools don't cover.
Volume first, then what goes in it, then what goes under or around it. Size the pour with the concrete calculator, count reinforcement from your plan's spacing with the rebar calculator, and figure base or backfill stone with the gravel tools. For masonry, count units first (block, brick, paver), then the mortar or sand those units consume — the unit calculators here do both in one pass.
Geometry and public formulas, computed live from what you enter — block core volumes from shell-and-web dimensions, mortar from joint geometry, rebar weights from the bar's diameter and steel's density. Nothing is copied from code tables, standards documents or any manufacturer's specs, and there are no built-in prices: cost fields use only the rates you type in.
No. Rebar spacing, wall heights, footing sizes and retaining-wall design are structural decisions governed by your project plans, local code, and an engineer where required. These calculators count materials for a design you already have — they don't produce the design.
No. The calculators run as JavaScript in your browser; your inputs never leave your device and there's no account or server involved.