Guides

In-depth, practical guides that answer the questions behind the calculations — each one links straight to the calculators you need.

6 min read How Much Concrete Do I Need? A Complete Ordering Guide Learn how to calculate concrete volume for slabs, footings and posts, when to order ready-mix vs bags, and how much extra to order. With worked examples. Read guide → 5 min read Paint Coverage Guide: How Far Does a Litre Really Go? How much area a litre or gallon of paint really covers, how surface type and colour changes affect coverage, and how to avoid buying too much or too little. Read guide → 6 min read How to Choose the Right AC Size for Any Room How to size an air conditioner: BTU per square metre, the factors that change the number, and why oversizing is as bad as undersizing. Read guide → 5 min read Tile and Flooring Buying Guide: Packs, Waste and Batches How to buy the right amount of tile, laminate and vinyl flooring: pack coverage, waste percentages by layout, and why batch numbers matter. Read guide → 7 min read Home Renovation Budget Guide: Where the Money Really Goes How to build a realistic renovation budget: cost per m² by quality tier, why kitchens and bathrooms break the curve, and how much contingency to keep. Read guide → 6 min read Solar Panel Sizing Guide: From Your Bill to Panel Count How to size a home solar system: read your kWh usage, find your sun hours, account for real-world losses and calculate panel count and roof area. Read guide → 6 min read How to Calculate Loan Payments: Amortization Explained Understand the loan payment formula, how interest and principal split over time, and how term length changes the total cost. With worked examples for mortgages and car loans. Read guide → 5 min read MPG vs L/100km: How to Compare Fuel Economy Why MPG and L/100km move in opposite directions, how to convert between them exactly, and how to turn fuel economy into real trip costs. With a conversion table. Read guide → 5 min read Profit Margin vs Markup: The Difference That Costs Money Margin and markup are not the same number. Learn both formulas, how to convert between them, and how to price products so you never confuse the two again. Read guide →