Order it right the first time
61 calculatorsTested formulasCited sources
Enter your measurements, get the bags, tons, yards or gallons to order — plus a cost estimate. Every formula is tested against worked examples and manufacturer figures.
Every calculator
Concrete, masonry & paving
Concrete in yards and bags, Portland cement mixes, block and brick counts with mortar, rebar and asphalt tonnage.
- Asphalt calculatorCalculate how many tons of hot-mix asphalt you need for a driveway, path or patch from length, width and compacted thickness, with cost per ton.
- Brick calculatorCalculate how many bricks you need for a wall — modular, standard, queen or king size — plus masonry cement and sand, with openings and waste.
- Cement calculatorMixing your own concrete? Find how many 94 lb bags of Portland cement, plus sand, gravel and water, you need for a slab or pad at 1:2:3 or 1:2:4.
- Concrete block calculatorCalculate how many concrete blocks (8x8x16 CMU) you need for a wall from its length and height, plus bags of mortar mix, with extra for breakage.
- Concrete calculatorWork out how much concrete you need for a slab, footing, wall, column or post holes — in cubic yards and 80, 60 or 40 lb bags, with waste included.
- Concrete slab calculatorEnter your slab's length, width and thickness to get cubic yards of concrete and the number of 80, 60 or 40 lb bags, plus an optional cost estimate.
- Concrete weight calculatorFind how much a concrete slab, pad, footing or column weighs in pounds, tons and kilograms from its size and thickness, for normal or lightweight concrete.
- Paver calculatorFind how many pavers you need for a patio, walkway or driveway, plus tons of gravel base, bedding sand and feet of edge restraint, with extra for cuts.
- Rebar calculatorCalculate how much rebar a concrete slab needs from its size and bar spacing — linear feet, 20 ft bars to buy, weight and ties for #3, #4 or #5 bar.
Landscaping & yard
Gravel, stone, mulch, compost, topsoil, sand, sod, seed, fertilizer, plants, fences and walls — how much to order for your yard.
- Compost calculatorWork out how much compost you need for new beds, existing beds and lawns in cubic yards and bags, using Oregon State Extension's application depths.
- Cubic yard calculatorConvert length, width and depth into cubic yards, cubic feet and cubic meters for soil, mulch, gravel, sand or concrete. Rectangles and circles.
- Dirt calculatorWork out how much fill dirt or topsoil to order for any area and depth, in cubic yards and tons, with extra for settling and an optional cost estimate.
- Fence calculatorEnter your fence length and post spacing to get the number of posts, rails and pickets, plus 80 lb bags of concrete to set the posts.
- Fence post calculatorCalculate how many fence posts you need with corners and gates, how long to buy them, how big to dig the holes and how much concrete to set them.
- Fertilizer calculatorCalculate how many pounds and bags of lawn fertilizer you need from your lawn size, the N-P-K numbers on the bag and the nitrogen rate.
- Fill dirt calculatorCalculate how much fill dirt you need to fill a hole, raise a yard or backfill — in cubic yards, tons and dump-truck loads, with compaction included.
- Grass seed calculatorCalculate how many pounds of grass seed you need for a new lawn or overseeding — tall fescue, Kentucky bluegrass, ryegrass mix or bermudagrass.
- Gravel calculatorFind how many tons and cubic yards of gravel, pea gravel, crushed stone or river rock you need for a driveway, path or base, with cost per ton.
- Mulch calculatorWork out how much mulch you need in cubic yards and 2 or 3 cu ft bags from your bed size and depth, with the depths extension services recommend.
- Pea gravel calculatorFind how much pea gravel you need for a patio, path or play area in tons, cubic yards and 0.5 cu ft bags, with an optional price per ton.
- Plant spacing calculatorCalculate how many plants fit in a bed or area from the spacing on the tag, in a square grid or staggered rows, with plants per square foot and cost.
- Raised bed soil calculatorCalculate how much soil you need to fill raised garden beds in cubic feet, cubic yards and bags, with the compost and topsoil split and extra for settling.
- Retaining wall calculatorCalculate retaining wall blocks, cap blocks, base gravel and drainage stone from wall length, height and block size, with a buried first course.
- River rock calculatorCalculate how much river rock you need for beds, borders and dry creek beds in tons, cubic yards and 0.5 cu ft bags, with an optional price per ton.
- Sand calculatorCalculate how much sand you need for a sandbox, paver base or fill in tons, cubic yards and 50 lb bags, with an optional price per ton.
- Sod calculatorWork out how much sod to order for your lawn in square feet, pallets, slabs or rolls, with extra for cuts and an optional price per pallet.
- Stone calculatorCalculate crushed stone, gravel, pea gravel or river rock in tons, cubic yards and 0.5 cu ft bags for a base, path or bed, plus a guide to stone sizes.
- Topsoil calculatorCalculate how much topsoil you need for a lawn or garden bed — in cubic yards for bulk delivery and in 0.75, 1 or 1.5 cu ft bags — with settling included.
Lumber & woodworking
Boards to buy, board feet, deck boards and joists, stair and stringer layout, and epoxy for table tops — lumber for wood projects.
- Board foot calculatorCalculate board feet for one board or a whole stack of lumber from thickness, width and length, with linear feet and an optional price per board foot.
- Deck calculatorCalculate how many deck boards you need from deck size, board width, gap and length, plus linear feet of decking, joists, deck screws and cost.
- Epoxy calculatorCalculate how much epoxy resin you need in gallons, ounces and liters for a table top, bar top or river table, split into resin and hardener by mix ratio.
- Lumber calculatorCalculate how many 2×4s, 2×6s or other boards to buy from your cut length and piece count, with saw kerf, offcuts, board feet and cost.
- Stair calculatorEnter the floor-to-floor rise to get the number of steps, riser height, total run, stringer length and angle, checked against IRC riser and tread limits.
- Stair stringer calculatorLay out cut stair stringers from the total rise, with riser and tread sizes, framing square marks, bottom riser cut, stringer length, board size and count.
Roofing & siding
Roofing squares, shingle bundles, roof pitch, rafter length and siding — what to order for a gable or hip roof and the walls under it.
- Rafter calculatorFind common rafter length for a gable roof from the building width, roof pitch and overhang, plus the lumber length to buy, cut angles and number of rafters.
- Roof pitch calculatorFind your roof pitch in inches per 12 from rise and run, ridge height and span, or the angle, with degrees, percent slope, pitch factor and shingle limits.
- Roofing calculatorCalculate roofing squares for a gable or hip roof from its footprint and pitch, with shingle bundles, underlayment, ice barrier, drip edge and cost per square.
- Shingle calculatorCalculate how many bundles of shingles you need for a gable or hip roof from its footprint and pitch, plus squares, starter strip, drip edge and ridge cap.
- Siding calculatorCalculate how much siding you need for a house in squares and boxes, from wall size and height, gable ends and roof pitch, minus doors and windows.
Walls, floors & paint
Paint, wallpaper, drywall, tile, flooring, carpet, grout and baseboard for a room: gallons, rolls, sheets, boxes and linear feet.
- Baseboard calculatorCalculate how much baseboard you need for a room in linear feet and 8, 12 or 16 ft pieces, with door openings taken out and extra for cuts.
- Carpet calculatorFind how much carpet to buy for a room in square feet and square yards, based on how it's cut from a 12 or 15 ft roll, plus pad and cost.
- Drywall calculatorFind how many 4x8, 4x10 or 4x12 drywall or wallboard sheets you need for a room, plus joint compound, tape and screws, with extra for waste.
- Flooring calculatorFind how much hardwood, laminate or vinyl plank flooring to buy for a room — square feet with waste, boxes, underlayment rolls, baseboard length and cost.
- Grout calculatorCalculate how much grout you need from tile size, thickness and joint width — in pounds and 25 or 7 lb bags — calibrated to a manufacturer coverage chart.
- Paint calculatorEnter the room size, doors, windows and coats to find how much paint you need — in gallons and quarts to buy — with an optional cost estimate.
- Tile calculatorFind how many tiles and boxes you need for a floor or wall from the room size, tile size and grout joint, with extra for cuts and an optional cost estimate.
- Wallpaper calculatorFind how many rolls of wallpaper a room needs from its size, wall height, doors, roll size and pattern repeat, using the strip method wallpaper hangers use.
Measurement & layout
Square footage, acreage, square yards, slope, tons to cubic yards and steel weight — measurements and conversions for estimating.
- Acreage calculatorConvert a lot's length and width into acres, square feet and hectares. Works for rectangles, triangles and circles, with an optional price per acre.
- Slope calculatorFind the slope between two points with the line's equation, angle and distance — or turn rise and run into grade %, angle, ratio and pitch.
- Square footage calculatorCalculate square feet for a room, floor, yard or lot — rectangles, L-shapes, triangles and circles — plus square yards, meters, acres and material cost.
- Square yard calculatorCalculate square yards from length and width in feet, inches or meters — for carpet, flooring, sod or concrete — with optional waste and price.
- Steel weight calculatorFind the weight of steel plate, round or square bar, tube and pipe — or aluminum, stainless, copper and brass — in pounds and kilograms, per foot and in total.
- Tons to cubic yardsConvert tons to cubic yards for gravel, crushed stone, sand, topsoil, fill dirt, asphalt and concrete, and see how many square feet the load covers.
Pool, heating & energy
Solar panels, AC BTUs, furnace size, attic insulation and electrical service size, plus pool volume, chlorine and salt doses.
- BTU calculatorFind the right air conditioner size in BTUs for a room from its square footage, sun exposure, number of people and kitchen use, using the ENERGY STAR chart.
- Electrical load calculatorEstimate a house's electrical load and service size in amps with the NEC 220.82 optional method, from living area, appliances, EV charger and heating or AC.
- Furnace size calculatorEstimate what size furnace your home needs in BTUs from its square footage, climate zone and insulation, and the input rating at your furnace's AFUE.
- Insulation calculatorFind how much attic or floor insulation to add for your climate zone — the ENERGY STAR R-value, the depth of blown fiberglass, cellulose or batts, and bags.
- Pool chlorine calculatorFind how much liquid chlorine, bleach, cal-hypo shock, dichlor or trichlor to add to raise your pool's free chlorine to the target ppm, from the pool's volume.
- Pool salt calculatorCalculate how many pounds and 40 lb bags of salt to add to your saltwater pool to reach your chlorinator's target ppm, from the pool's volume and current level.
- Pool volume calculatorFind how many gallons your pool holds — rectangle with shallow and deep ends, round or oval — plus liters, cubic feet and the salt for a fresh fill.
- Solar panel calculatorFind how many solar panels you need and what size system, from your state's sunshine (NREL data), your monthly electricity use and the panel wattage.
How the numbers are graded
- TestedEvery formula runs against hand-worked answers before it ships.How we test
- SourcedBag yields, densities and coverage rates come from manufacturer data sheets, cited on each page.The constants
- ShownEach calculator works a full example with the same numbers, so you can check it by hand.An example