FREE CALCULATORS · NO SIGN-UP
Free Home Improvement & Appliance Calculators
Work out exactly what your project needs — concrete, paint, flooring, fencing and more — with calculators that show their formulas and worked examples. No guesswork, no sign-up, free forever.
Concrete Calculator — try it now
Slabs, footings and post holes — volume, bags and cost in seconds.
Choose a shape, enter your dimensions, and the results update as you type — or press Calculate.
Enter your dimensions, then press Calculate.
Formulas: rectangle = length × width × thickness; circle = π × radius² × thickness; post hole = π × radius² × depth × number of holes; yd³ = cu ft ÷ 27; bags = volume with waste ÷ bag yield, rounded up.
Every calculator shows its formula and a worked example. Estimates only — see our Disclaimer.
All Calculators
34 free tools — pick your project, get your materials list.
Yard & Outdoor
12 toolsConcrete Calculator
Volume, bags and cost for slabs, footings and post holes.
Popular🌾Mulch Calculator
Bags or bulk yards for garden beds, with a depth guide.
🪨Gravel Calculator
Tons and cubic yards for driveways, paths and bases.
🌱Topsoil Calculator
Cubic yards and bags for raised beds and new lawns.
🪵Fence Calculator
Posts, rails and pickets for any fence length.
🔨Deck Calculator
Boards, joists, posts and screws for your deck size.
🟫Paver Calculator
Pavers plus sand and gravel base for patios and paths.
🌿Sod Calculator
Rolls and pallets of turf for an instant new lawn.
🏗️Retaining Wall Calculator
Blocks, caps and backfill gravel for garden walls.
🏊Pool Volume Calculator
Gallons and litres in rectangular, round and oval pools.
💧Irrigation Calculator
Sprinkler and drip run times, and gallons per week.
🌲Bark Mulch Calculator
Litres and bags of bark for UK beds and borders.
Floors, Walls & Roof
8 toolsFlooring Calculator
Boxes of laminate, vinyl or hardwood, waste included.
Popular🎨Paint Calculator
Gallons and coats for rooms and whole houses.
Popular🔲Tile Calculator
Tiles, grout and adhesive for floors and walls.
🖼️Wallpaper Calculator
Rolls needed, with pattern-repeat allowance.
▦Drywall Calculator
Sheets, mud and screws for walls and ceilings.
🏠Roofing Calculator
Shingles, bundles and squares for any roof pitch.
🌡️Insulation Calculator
Depth, bags and R-value for attics and walls.
🧱Plasterboard Calculator
UK sheets for walls and ceilings, worked out in metres.
Appliances, HVAC & Energy
8 toolsRepair vs Replace Calculator
Repair or replace? A clear verdict from the costs.
⚡Electricity Cost Calculator
Running cost of any appliance — per hour, month or year.
❄️AC BTU Calculator
The right air-conditioner size for your room.
☀️Solar Panel Calculator
Panels, system size, cost and payback for 2026.
🚿Water Heater Size Calculator
The tank size and first-hour rating your home needs.
🔥Heating Cost Calculator
What electric, heat pump and gas heating cost to run.
💡LED Savings Calculator
Savings from switching your bulbs to LED, with payback.
🧊Fridge Running Cost Calculator
What your fridge costs per day, month and year.
Measure, Convert & Costs
6 toolsSquare Footage Calculator
Area of rooms and shapes — rectangles, triangles and circles.
📦Cubic Yard Calculator
Volume in yards, cubic feet and metres for bulk materials.
🪚Board Foot Calculator
Lumber volume and cost from board dimensions.
🧾Cost per Square Foot Calculator
Compare quotes and materials at a fair per-foot rate.
🔄Unit Converters
Square feet to m², gallons to litres and more, both ways.
🛠️Remodel Budget Calculator
Room-by-room remodel budgets with contingency built in.
How it works
Measure your space
Length, width and depth or height — the tool handles the units.
Enter the numbers
Imperial or metric, with waste and cutting allowances included.
Get your materials list
Quantities in bags, yards, tons or gallons — ready to order.
Why Wolveyes?
Formulas shown
Every result shows the maths behind it, so you can check it yourself.
Imperial & metric
Switch between feet and metres on every calculator, any time.
Prices for US · UK · CA · AU
Built-in electricity prices for the four countries our readers live in.
Free, no sign-up
No account, no email address, no catch — just the numbers.
Frequently asked questions
Are these calculators really free?
Yes — all 34 calculators are completely free to use, with no sign-up, no account and no limits.
How accurate are the results?
They use the same formulas tradespeople use, with waste allowances built in. Treat the numbers as solid estimates for budgeting and ordering, and have any structural work checked by a professional.
Can I switch between imperial and metric?
Yes — every calculator has a unit toggle, so you can work in feet and inches or metres and centimetres.
Which countries are the prices for?
Electricity prices are built in for the US, UK, Canada and Australia. The material quantities themselves work anywhere in the world.
What should I calculate first for a renovation?
Start with the biggest material cost — usually concrete, flooring or paint — then work down the list. Our guide to calculating building materials for a site walks through the full order step by step.