Free financial planning tools
SMO Financial Calculator
Turn everyday money questions into clear numbers. Calculate loans, savings, taxes, salary, percentages, and discounts with transparent formulas.
Calculator directory
Plan every side of your finances
Loan Calculator
Estimate monthly loan payments, total interest, and the full repayment cost with a clear principal-versus-interest breakdown.
Calculate nowSavings Calculator
Project how your savings can grow with an opening balance, regular deposits, interest, and time.
Calculate nowTax Calculator
Estimate income tax with a configurable tax rate and deductions, then see your effective rate and after-tax income.
Calculate nowSalary Calculator
Convert pay between hourly, weekly, monthly, and annual amounts and estimate take-home income after deductions.
Calculate nowPercentage Calculator
Solve common percentage questions, including percent of a number, percentage change, and part-to-whole ratios.
Calculate nowDiscount Calculator
Calculate a sale price, stacked discounts, tax, and your total savings before you buy.
Calculate nowFinancial education
Understand the numbers behind your money
Income & Salary · 9 min
How Salary Calculations Work: From Hourly Rate to Take-Home Pay
A step-by-step guide to converting hourly pay, salaries, overtime and pay periods into real take-home pay, with an interactive converter and worked examples.
Income & Salary · 9 min
Gross vs Net Income Explained: What Really Comes Out of Your Pay
Learn the difference between gross and net income, every common payroll deduction, and how to estimate take-home pay with an interactive breakdown and US and UK examples.
Taxes · 11 min
Income Tax Explained: How Tax Brackets, Deductions and Effective Tax Rates Actually Work
A clear guide to income tax: taxable income, deductions, progressive brackets, marginal and effective rates, with a bracket calculator and dated US, UK and Spain examples.
Taxes · 10 min
Marginal vs Effective Tax Rate: What Really Happens When You Get a Raise
See exactly how a raise is taxed with an interactive simulator, a bracket-by-bracket breakdown, and the exceptions — payroll contributions, allowance tapers and benefit phase-outs.
Budgeting · 10 min
Smart Shopping: How to Calculate Real Discounts and Avoid Sale Traps
Learn how to calculate sale prices, stacked discounts, and tax, and recognise common marketing tactics that make deals look better than they are.
Budgeting · 10 min
The 50/30/20 Budget Rule: How to Use It and When to Adapt It
Learn how the 50/30/20 budget rule divides income into needs, wants, and savings, with examples and adaptations for high-cost areas and debt.
Frequently Asked Questions
- Yes. Every calculator is free, requires no account, and can be used as often as you need.
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