About CalculatorDashboard

Why we built this

Most financial websites are either too complicated, full of sales pitches, or written by people who've never had to worry about whether they're saving enough, earning enough, or making the right pension choices. We built CalculatorDashboard because we wanted somewhere we could actually trust — a place that gives you the maths and explains it in plain English, so you can make your own informed decisions.

What you'll find here

A growing library of calculators covering the financial decisions that matter most to people in the UK — from income tax and take-home pay, to compound interest, pension projections, drawdown scenarios, mortgage costs, and more. Every calculator is free. Every result comes with a plain-English explanation of what it means for you. No login. No paywall. No ads telling you what to do with your money.

Who's behind it

CalculatorDashboard is an independent project. We're not a bank, an IFA, or an affiliate site. We don't earn commission on what you do with your money. The calculators are built on publicly available UK data (HMRC rates, ONS figures, Bank of England base rate) and updated when the numbers change.

How the calculators work

Every calculator on this site is built to show its working, not just spit out a number. Where a calculation depends on assumptions — an interest rate, an inflation figure, a rate of investment growth — we tell you what we assumed and, wherever possible, let you change it. The defaults are chosen to be reasonable and clearly labelled, never hidden.

Projections are not guarantees. Any calculator that looks into the future — pension drawdown, compound interest, FIRE and early-retirement tools, mortgage overpayment — is modelling one possible path, not predicting what will actually happen. Real returns, inflation, tax rules and your own circumstances will differ. Treat the outputs as a way to compare scenarios and understand the shape of a decision, not as a promise of a specific outcome.

How we model market risk (sequence of returns)

Most retirement calculators assume your investments grow by the same smooth percentage every year — say 5% — as if the market rose in a straight line. Real markets don't work that way, and the order in which good and bad years arrive matters enormously once you're drawing an income. This is called sequence-of-returns risk: two people with the same average return over 30 years can end up with wildly different outcomes simply because one hit a market crash in their first few years of drawing down and the other didn't.

Rather than flatten that risk away with a single average, our retirement and drawdown tools stress-test your plan against real historical market sequences — actual runs of S&P 500 total returns going back to 1957, adjusted for UK inflation. That shows you not just the rosy middle case, but how your plan would have held up if you'd retired into one of history's worse starting points. It's a more honest picture of the risk you're actually carrying.

Data sources

The calculators are built on publicly available, authoritative data, and updated when the numbers change. Our main sources are:

Tax, National Insurance & allowances — HMRC / GOV.UK, using the published rates and thresholds for the relevant tax year.
Interest & base rate — the Bank of England official Bank Rate.
Inflation (CPI) — the Office for National Statistics.
Historical investment returns — long-run S&P 500 total-return data (since 1957), used to model real market sequences rather than flat averages.

Get in touch

Have a question, spotted an error, or want to suggest a calculator we should build? We'd love to hear from you.

Email: info@calculatordashboard.com