UK financial calculators · free & private

Make the big money calls with actual maths.

Four calculators that model UK student loans, mortgages, car finance and your pay packet properly — so you can see which choice genuinely leaves you wealthier, not just which one feels right.

5 UK loan plans modelled £0 cost, no sign-up 100% in your browser
Four tools, one suite

Pick the decision you’re weighing up.

Each calculator is built on real UK rules and updates live as you change your numbers.

Student Loan Strategy

Should you overpay your student loan — or invest instead?

UK student loans aren’t normal debt. We model income-based repayments, RPI interest and the write-off date, then compare four strategies side by side so you know which builds the most wealth.

  • Plan 1, 2, 4, 5 & Postgraduate — correct thresholds and write-off rules
  • Standard vs overpay vs lump sum vs invest, ranked by net wealth
  • A plain-English verdict: “invest the £250/mo and you’re £612k wealthier”
Open Student Loan Calculator
Recommended
Net wealth at write-off
£612,480
Invest
Overpay
Lump
Standard
Written off£201,340
Cleared byWrite-off · yr 40
PCP Calculator

See the true cost of a car finance deal before you sign.

Personal Contract Purchase hides a lot. We break down the monthly payment, the optional final “balloon”, total interest and the real cost of ownership — and compare PCP against a loan or paying cash.

  • Monthly payment, balloon (GMFV) and total payable, instantly
  • Deposit, part-exchange and dealer contribution all factored in
  • PCP vs bank loan vs cash — which is cheapest over the term
Open PCP Calculator
Your deal
Estimated monthly payment
£442/mo
Deposit Interest Balloon
Term · APR48 mo · 9.9%
Final balloon (GMFV)£12,400
Total payable£33,616
Mortgage Strategy

Overpay the mortgage, or invest the difference?

The biggest money question most homeowners face. We model your real mortgage — repayment or interest-only, fixed-then-SVR rates, the 10% overpayment rule — and show whether overpaying or investing the same cash leaves you wealthier by the end of the term.

  • Repayment & interest-only, with a fixed rate that reverts to the SVR
  • Overpay vs invest, side by side — plus the 10% ERC warning
  • Stamp duty & an affordability check baked in
Open Mortgage Calculator
£225k · 4.5% · 30y
Verdict · £250/mo spare
Invest it
Overpay
Invest
Interest saved by overpaying£107k
Investment pot instead£402k
Net advantage+£295k
Take-Home Pay

Know exactly what lands in your account each month.

Enter your salary and see the full picture: Income Tax, National Insurance, pension and student loan — all stripped out, with the real keep-rate. Models England/Wales/NI and Scottish bands.

  • Income Tax, NI, pension & student loan — broken down to the pound
  • Salary-sacrifice vs net-pay pensions, and the £100k “60% trap”
  • Per year, month or week — and your true marginal rate
Open Take-Home Pay
£45,000 salary
Take-home · per month
£2,725
Take-home Tax NI Loan Pension
Keep-rate72.7p in every £1
Effective tax rate22.3%
Why bother

Built to be trusted, not to upsell.

£

Genuinely UK-accurate

Real thresholds, repayment rates, RPI interest and write-off timelines — updated from a central config each year.

Live recalculation

Drag a slider and every chart, figure and recommendation updates instantly. No “calculate” button.

No jargon, no fear

Plain-English verdicts that explain the why — not scare tactics or get-rich-quick nonsense.

Private by design

Everything runs in your browser. Your salary and balances never leave your device.

Big money decisions, made with real clarity.

Start with whichever applies to you. Every tool is free, takes a couple of minutes, and might change what you do with the next few thousand pounds.