Methodology
See how the calculators work, what they include and where we have had to keep things simple.
UK planning tools
Pick a calculator and start with your own numbers.
Each calculator is built around a specific decision. The three decision tools at the top are the ones most people come to the site for; the others help with the planning around them.
Flagship planning tool
Wealth Planner
Project your full wealth picture over time using savings, investments, pension and property equity. Includes milestone ages, visual charts and ONS household wealth benchmarks.
Start here
Decision tools
These calculators are built around choices where the useful answer often depends on assumptions and trade-offs.
Pension contributions and take-home pay
Salary Sacrifice Calculator
Estimate how pension salary sacrifice could affect tax, National Insurance, take-home pay and pension contributions in the 2026/27 tax year.
Debt repayment or investing
Mortgage vs Invest Calculator
Compare overpaying your mortgage with investing spare cash, including ISA, pension and taxable investment assumptions.
Tax wrapper decision
ISA vs Pension Calculator
Compare ISA flexibility against pension tax relief, including basic-rate, higher-rate and salary sacrifice scenarios.
Planning calculators
Use these to build a fuller picture around retirement, drawdown and your cash buffer.
Looking ahead to retirement
Retirement Calculator
Estimate what a retirement pot could look like by a chosen age using contributions, growth and inflation assumptions.
Taking income from a pot
Drawdown Calculator
Model how long a pot could last when regular withdrawals are taken, and how assumptions change the outcome.
Building a cash buffer
Emergency Fund Calculator
Estimate a practical emergency fund target based on essential monthly spending and your chosen safety margin.
Understanding where you stand
Net Worth Calculator
Add up your assets and subtract your debts to find your current net worth. See how it compares to UK averages for your age group using ONS data.
Your State Pension entitlement
State Pension Calculator
Estimate your weekly, monthly and annual State Pension based on your National Insurance qualifying years. Includes deferral comparison. 2026/27 figures.
Growth calculators
Two straightforward tools for projecting how savings and investments could grow over time.
Investing over time
Investment Calculator
Project investment growth, monthly contributions and inflation-adjusted values over a chosen time period.
Saving towards a target
Savings Calculator
Work out how long it could take to reach a savings target, including regular deposits and interest assumptions.
How to read the results
Use the calculators to run different scenarios based on your current and future goals. The numbers are a guide, not a final answer; come back and update them whenever your situation changes.
Knowledge Hub
Read the background guides that explain the trade-offs behind the tools.
Spot something?
If a number or a link looks wrong, get in touch and we will look into it.