Practical guides: calculations explained step by step
Clear explanations with worked examples for the calculations people make most: salary, VAT, loans, tax, grades, BMI…
Gross to net salary in Belgium (2026): how it worksSocial security (ONSS), withholding tax and municipal tax: how a Belgian gross salary becomes take-home pay, with examples for €2,200, €3,000 and €4,500.Read the guide →How to calculate VAT: add it or remove it the right wayThe formulas to add or remove VAT, current rates in the UK, Belgium, France and Switzerland, and the most common mistake when taking VAT off a price.Read the guide →Loan amortization schedule: how your monthly payment worksHow a loan's monthly payment is calculated, why early payments are mostly interest, and how to read an amortization schedule, with worked examples.Read the guide →How much can I borrow for a home?The debt-to-income ratio, term and interest rate that decide how much a bank will lend you, with a worked example.Read the guide →French income tax 2026: brackets, parts and a step-by-step exampleThe 2026 French income tax brackets (2025 income), the family quotient, the cap and the tax reduction (décote) explained with worked examples.Read the guide →How to calculate percentages: the 4 everyday casesX% of a number, what percent one value is of another, percentage change, and reversing a percentage: simple formulas and examples.Read the guide →Weighted average and the grade you need on your final examHow to calculate a weighted average and what score you need on the final exam to pass or hit your target, with step-by-step examples.Read the guide →Break-even point: how much you need to sell to stop losing moneyHow to calculate the break-even point in units and revenue, with the contribution margin and a full worked example.Read the guide →BMI: how to calculate it and what the result meansThe body mass index formula, the WHO categories, a worked example and the limits of BMI.Read the guide →Property buying costs in Belgium and France: taxes and notary feesWhat buying a home costs on top of the price in Wallonia, Brussels, Flanders and France, with 2026 rates and examples.Read the guide →