Buy vs Rent
Model the true cost of buying versus renting over your chosen time horizon — including stamp duty, mortgage costs, and the opportunity cost of your deposit.
Open calculatorFinancial Calculators
Free UK financial calculators — no sign-up required.
Important: The calculators on this page are for informational and illustrative purposes only. They do not constitute regulated financial advice. Results are based solely on the inputs and assumptions you provide — they are not predictions or guarantees of future outcomes. Tax rules, rates, and allowances are subject to change and may not reflect your individual circumstances. Selvox accepts no liability for decisions made in reliance on these outputs. If you are unsure about any financial decision, speak to a regulated financial adviser.
Income Tax & NI Calculator
See your take-home pay, tax band breakdown, and effective rates for 2026/27. Scottish rates included.
Open calculator →Platform Fee Calculator
Compare Vanguard, HL, AJ Bell and others. See how fees compound over decades.
Open calculator →Retirement Calculator
10,000 Monte Carlo simulations using 125 years of UK market data.
Open calculator →Compound Interest
See how your investments grow over time with the power of compounding.
Open calculator →Salary Sacrifice
Calculate your NI saving and the true net cost of pension contributions.
Open calculator →ISA vs SIPP
Compare after-tax outcomes. See when 40% tax relief makes the SIPP a clear winner.
Open calculator →State Pension
Estimate your State Pension from qualifying NI years and see the deferral bonus.
Open calculator →Safe Withdrawal Rate
Find your UK safe withdrawal rate. Why the US 4% rule does not apply here.
Open calculator →Mortgage Calculator
Monthly payments, total interest, LTV, and the true cost of your mortgage.
Open calculator →Director Pay Calculator
Find the most tax-efficient salary, dividend, and pension mix for limited company directors.
Open calculator →Redundancy & Settlement
Calculate statutory pay, your £30,000 tax-free allowance, and how much of your settlement you'll actually keep.
Open calculator →Junior ISA (JISA)
Model tax-free growth for your child's Junior ISA from birth to 18. See the allowance cap, the tax advantage over a taxable account, and the cost of starting late.
Open calculator →Emergency Fund
Calculate your personalised emergency fund target and how long it will take to reach it based on your expenses and circumstances.
Open calculator →FIRE Number Calculator
Calculate how much you need to retire early. Model your safe withdrawal rate, State Pension offset, and year-by-year path to financial independence.
Open calculator →Student Loan Calculator
Model your loan balance, repayment timeline, and whether voluntary overpayments are actually worth making — or whether your loan will write off anyway.
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