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Finance
Compound interest: starting capital, return and timeUnderstand compound interest and how capital, return, contributions and time work together.Dividend planning: payouts, yield and incomeUnderstand dividends, yield, taxes and recurring investment income.ETF savings plan: build wealth over the long termETF savings plan explained: monthly contribution, time horizon, return, fees, compound growth and common mistakes with examples and calculator.Extra repayments: shorten the term or lower the paymentPlan extra repayments and understand their effect on balance, interest and term.Financial independence: target wealth, savings rate and withdrawal ratePlan FIRE with realistic target wealth, savings rate, returns and withdrawal assumptions.Home budget: purchase price, equity and affordable paymentEstimate how much home fits your income, equity and monthly budget.Home purchase costs: transfer tax, notary and agent feesUnderstand the additional costs that come with buying a home.Hourly wage and annual salary: convert hours, days and payConvert between hourly wage and annual salary using working hours and yearly assumptions.Hourly wage: salary, working time and real payCalculate hourly wage using salary, working hours, holidays and real workload.Household budget: income, expenses and financial roomStructure your household budget and identify fixed costs, variable expenses and savings potential.Inflation explained: purchasing power, price increases and real valueCalculate inflation and understand how prices affect purchasing power over time.Labor costs: wages, payroll costs and total employer expenseCalculate labor costs realistically and understand the true cost of employment.Lease payment: down payment, term and residual valueEvaluate leasing costs including payment, mileage, residual value and total cost.Mortgage planning: interest, repayment and total costPlan a mortgage realistically and understand monthly payments, repayment and total cost.Net to gross salary: plan target income and deductionsCalculate the gross salary needed for a target net income.Property return: rent, expenses and net yieldCalculate property returns realistically including income, expenses, financing and risk.Purchasing power: inflation, income and real valueCompare purchasing power and understand the real value of money over time.Rent or buy: compare costs, equity and time horizonCompare renting and buying fairly across monthly cost, equity, value growth and risk.Repayment planning: balance, loan term and interest costUnderstand how repayment rate, monthly payment and interest affect remaining debt.Retirement gap: income need, pension and savings rateEstimate a retirement income gap and plan savings needs realistically.Return calculation: profit, time horizon and annualized returnCalculate investment returns using profit, time, costs and comparison values.Salary calculation: gross, net and deductionsUnderstand gross salary, net pay, taxes and social security deductions.Savings goal: contribution, duration and target amountPlan a savings goal with starting amount, regular contribution and time horizon.Tax class: net income, household model and wage taxUnderstand how tax class affects net income and payroll tax.Understanding loan costs: monthly payment, interest and total repaymentUnderstand loan costs clearly: how monthly payment, interest rate, term, fees and total repayment work together – with checklist and calculator.
Category
Energy
Apartment heating costs: monthly and per-square-meter guideUnderstand apartment heating costs per month, per year and per square meter. Learn what affects heating expenses.CO₂ costs: emissions, carbon price and yearly impactCalculate CO₂ costs and understand how emissions and carbon prices affect expenses.EV or combustion car: compare cost, energy use and daily drivingCompare EVs and combustion cars fairly across purchase cost, energy, maintenance and running costs.Gas usage: kWh, payments and heating costUnderstand gas usage, unit price, base fees and yearly costs.Heat pump calculation: electricity use, efficiency and heating costEvaluate heat pump costs using seasonal efficiency, electricity price and heat demand.How to save electricity costs: find power-hungry devicesSave electricity costs with practical examples, clear thresholds and useful actions: check appliances, classify usage, review tariffs and estimate realistic savings.Save heating costs: reduce consumption and expensesPractical tips to save heating costs: reduce usage, ventilate properly, optimize room temperature, understand fixed costs and calculate heating expenses.Understand balcony solar: when does plug-in solar pay off?Balcony solar pays off through electricity used at the same time it is generated. Generated power is not automatically savings.Understand solar + heat pump: how well do they really fit?Solar and heat pumps fit technically, but not perfectly in time: heating demand is high in winter when solar generation is low.Understand solar autonomy: how independent can solar really make you?Autonomy is not a return metric. It shows how much demand is covered by PV and battery and how much grid import remains.Understand solar batteries: when does storage really pay off?Understand solar batteries: self-consumption, payback, lifetime value and a clear decision logic.Understand solar EV charging: when does your car really charge from PV?Solar EV charging only works well when surplus, charging time and driving profile match. This guide separates annual PV yield from usable charging energy.Understand solar PV: does your PV system really pay off?Evaluate solar PV realistically: yield, self-consumption, feed-in without battery, grid import, annual value and payback.Understand solar system size: what size fits your household?The right PV size is not automatically the largest possible system. Generation, consumption, roof space, battery and budget need to fit together.
Category
Everyday
Age calculator: years, months and days clearly explainedCalculate age accurately and understand years, months, days and reference dates.Date calculation: deadlines, periods and reference datesCalculate dates, count days and plan deadlines more reliably.Emergency fund: savings buffer, fixed costs and safety monthsPlan an emergency fund based on fixed costs and financial safety needs.Fuel costs: consumption, distance and fuel priceCalculate fuel costs using consumption, distance and price per liter.Overtime calculation: time balance, premiums and compensationCalculate overtime with working hours, premiums, time off and payout options.Percentage calculation: share, change and comparisonCalculate percentages, discounts, increases and changes correctly.Vacation entitlement: working days, part-time and remaining leaveCalculate vacation entitlement using working days, employment periods and part-time work.VAT calculation: net, gross and tax rateCalculate VAT and convert between net and gross amounts correctly.Working time: calculate hours, breaks and daily schedulesCalculate working time clearly with start time, breaks, end time and total hours.
Category
Health
Basal metabolic rate: energy needs and daily contextUnderstand BMR, calorie needs, activity level and personal goals.BMI explained: weight, height and health contextUse BMI sensibly and understand what it can and cannot tell you.Calorie needs: BMR, activity and goal planningCalculate calorie needs with BMR, activity level and personal goals.