Free UK Financial Calculators 2025/26

CalcToolkit provides free, accurate UK financial calculators for 2025/26. Calculate your take-home salary after tax, compare IR35 contractor options, work out fuel and EV running costs, plan mortgage repayments, understand your home equity, and see the true cost of credit card debt. All calculations run entirely in your browser — no sign-up required.

UK Salary Calculator 2025/26

Calculate your take-home pay after income tax, National Insurance, student loan repayments and pension contributions. Covers all student loan plans (Plan 1, 2, 4 and Postgraduate), salary sacrifice and relief at source pension schemes, and the personal allowance taper above £100,000. Updated for 2025/26 tax rates.

Income tax at 20%, 40% and 45% rates
Employee National Insurance at 8% and 2%
Student loan Plans 1, 2, 4 and Postgraduate
Salary sacrifice and relief at source pensions

IR35 Calculator 2025/26 – Umbrella vs Ltd Company

Compare your take-home pay inside IR35 via an umbrella company against outside IR35 via your own limited company. Enter your hourly, daily, weekly, monthly or annual contract rate. Updated for the April 2025 employer National Insurance increase to 15%.

Supports hourly, daily, weekly, monthly and annual rates
Umbrella company fee deduction
Employer NI at 15% (from April 2025)
Ltd company salary + dividend optimisation
Corporation tax, dividend tax and personal allowance

Fuel & EV Cost Calculator – Petrol, Diesel and Electric

Calculate the cost of any journey for petrol, diesel and electric vehicles and compare all three side by side. Work out your real-world MPG from a journey, or find your EV's range and charging cost. Supports miles and kilometres, MPG and L/100km, and pence per kWh for electric vehicles.

Side-by-side petrol, diesel and EV cost comparison
MPG and L/100km fuel efficiency calculator
EV range and charging cost calculator
CO₂ emissions estimate for petrol and diesel

Mortgage Repayment & Home Equity Calculator

Calculate your monthly mortgage repayments for capital and interest or interest-only mortgages. See how overpayments reduce your total interest and shorten your term. The home equity tab shows your LTV ratio, how much equity you have, and how far you are from key remortgage thresholds at 60%, 75%, 85%, 90% and 95% LTV.

Capital and interest or interest-only repayment types
Monthly overpayment savings calculator
Year-by-year amortization schedule
Home equity and LTV remortgage threshold calculator
Property value change scenario modelling

Credit Card Interest Calculator

See exactly how long it takes to clear your credit card balance, how much total interest you will pay, and the difference between making minimum payments versus paying a fixed amount each month. The payment comparison table shows minimum payments, your chosen amount, and double your payment side by side.

Time to clear debt at any monthly payment
Total interest paid over the repayment period
Minimum payment vs fixed payment comparison
UK standard minimum payment calculation (1% + interest, min £25)