Home Calculators

Free Home Improvement Calculators — Plan Your Project with Confidence

Home improvement projects — whether you're repainting a bedroom, retiling a bathroom, laying a gravel path, or pouring a concrete slab — always involve materials estimation. Ordering too little means costly return trips to the hardware store; ordering too much wastes money. Our free paint calculator, tile calculator, gravel calculator, and concrete volume calculator are designed to give you accurate material estimates in seconds, so you can plan and budget your project with confidence before you buy a single tin or bag.

Paint Calculator — Exactly How Many Litres You Need

One of the most common mistakes in DIY painting is buying the wrong amount of paint. Our online paint calculator takes the length, width, and ceiling height of your room, accounts for windows and doors, and calculates the exact number of litres required for one or two coats. It factors in the standard paint coverage rate (approximately 10–12 m² per litre for emulsion). Whether you're painting a single feature wall or a whole house, the calculator gives you a precise shopping list. It also helps you compare coverage across different paint brands or grades.

Tile Calculator — Never Run Short (or Overbuy)

Tiling requires careful planning — buy too few tiles and your batch number won't be available at the next shop. Our tile quantity calculator lets you enter the dimensions of the area you're tiling (floor or wall) and the size of your chosen tile, and instantly calculates how many tiles you'll need, including a 10% wastage buffer for cuts, breakages, and future repairs. This buffer is especially important for diagonal or pattern laying, where cut wastage is significantly higher. The calculator works in metres, centimetres and square feet.

Tile Cost Calculator — Budget Your Tiling Project

Once you know your tile count, use our tile cost calculator to estimate the full project spend — tile material, adhesive, grout, and optional labour cost. The calculator works in m² or sq ft, supports multiple currencies, and breaks the cost down line by line so you know exactly where your money is going before you buy anything. It's ideal for bathroom tiling cost estimates, kitchen floor budgets, and full-house tiling projects.

Concrete Volume Calculator — Slabs, Footings & Columns

Concrete is sold by the cubic metre (m³) or cubic yard, so knowing your volume accurately is essential before hiring a transit mixer or ordering ready-mix. Our concrete calculator covers three common structural shapes: rectangular slabs (driveways, patios, floor slabs), circular slabs (garden stepping stones, columns), and rectangular footings (fence posts, foundation walls). Enter the dimensions, and the tool outputs the required volume in m³ along with a 5% recommended overage to account for spillage and uneven ground. This is particularly useful for DIY foundations, garden projects, and small construction work.

Gravel Calculator — Pathways, Driveways & Drainage Beds

Loose aggregate projects are easy to underestimate without a proper volume-to-weight conversion. Our gravel calculator lets you input length, width, and depth in metric or imperial units, choose material density, and instantly get results in cubic metres, cubic feet, kilograms, tons, and bag count. It also includes a wastage buffer so you can plan for compaction and uneven surfaces. This is useful for landscaping beds, driveway topping layers, French drains, and utility backfill planning.

Plan Smarter, Spend Less

Good planning is the single biggest factor in keeping a home renovation project on budget. Use our calculators before you visit the hardware store — not after. For more tools, explore our finance calculators (including a home loan EMI calculator), or browse all free tools on civvy.tech.

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