Finance Calculators
Browse our collection of free online finance calculators — built to help you make smarter money decisions in seconds. Whether you’re planning a loan, calculating mortgage payments, estimating investment growth, or working out VAT, our tools give you fast, accurate answers with no sign-up required.
Our Free Finance Calculators
- UK £100k Tax Trap Calculator
- Mileage Calculator — Estimate travel cost, business mileage, fuel usage, MPG, and mileage reimbursement
- Loan Calculator — Calculate monthly repayments and total interest on any loan
- Mortgage Calculator — Estimate monthly mortgage payments and full repayment cost
- Compound Interest Calculator — See how your savings and investments grow over time
- Interest Calculator — Calculate simple interest on loans or savings
- APR Calculator — Find the true cost of any loan using Annual Percentage Rate
- Savings Calculator — Calculate how much your savings will grow
- ROI Calculator — Measure return on investment for any project
- Discount Calculator — Find the sale price after any percentage discount
- Percentage Calculator — Solve any percentage problem instantly
- VAT Calculator — Add or remove VAT from any price
- Salary Calculator — Convert between annual, monthly, and hourly pay
Why Use a Finance Calculator?
Financial decisions are some of the most consequential choices you’ll ever make — and even small errors in calculation can cost you thousands over time. A 0.5% difference in a mortgage interest rate on a £250,000 loan adds up to over £15,000 extra over 25 years. Understanding your loan terms, monthly commitments, and investment returns before you commit isn’t just helpful — it’s essential.
How Loan and Mortgage Calculations Work
Most loans use an amortisation schedule — each monthly payment covers both interest and a portion of the principal. Early payments are heavily weighted toward interest; as the balance reduces, more of each payment goes toward the principal. Our Loan Calculator and Mortgage Calculator show you the full breakdown of every payment over the life of the loan.
Understanding APR vs Interest Rate
The headline interest rate on a loan tells you only part of the story. The Annual Percentage Rate (APR) includes the interest rate plus any fees, charges, and costs — giving you the true cost of borrowing. By law, lenders in the UK must advertise their APR. When comparing loans, always compare APR rather than the nominal interest rate. Our APR Calculator helps you calculate and compare the true cost of any loan.
The Power of Compound Interest
Compound interest means earning interest on your interest — and over time, the effect is dramatic. £10,000 invested at 7% annual compound interest grows to over £76,000 in 30 years without any additional contributions. Our Compound Interest Calculator shows you exactly how your money grows based on your rate, frequency, and time period.
Finance Calculation Quick Reference
| Calculation | What It Tells You | Our Tool |
|---|---|---|
| Monthly loan repayment | How much you’ll pay each month | Loan Calculator |
| Total interest paid | True cost of borrowing over time | Loan Calculator |
| Compound growth | Future value of savings or investments | Compound Interest Calculator |
| APR | True annual cost including fees | APR Calculator |
| VAT amount | Tax to add or remove from a price | VAT Calculator |
| ROI percentage | Return on any investment | ROI Calculator |
| Fuel cost & mileage reimbursement | Travel cost, MPG, and cost per mile | Mileage Calculator |
Frequently Asked Questions
How do I calculate monthly loan repayments?
The formula for monthly repayments is: M = P × [r(1+r)^n] ÷ [(1+r)^n − 1], where P is the loan principal, r is the monthly interest rate, and n is the number of payments. Our Loan Calculator does this instantly — just enter your loan amount, interest rate, and term.
What is the difference between simple and compound interest?
Simple interest is calculated only on the original principal. Compound interest is calculated on the principal plus all accumulated interest — meaning the balance grows faster over time. Most savings accounts and investments use compound interest; most consumer loans use amortised repayments that are structurally similar to compound interest from the lender’s perspective.
How is VAT calculated in the UK?
UK standard VAT rate is 20%. To add VAT: multiply the net price by 1.20. To remove VAT from a gross price: divide by 1.20. Our VAT Calculator handles both directions instantly and also supports the reduced 5% VAT rate.
Most Popular Finance Calculators
Our most-used tools are the loan calculator, mortgage calculator, and compound interest calculator — used by thousands of people every month to plan major financial decisions. Planning a work trip or road journey? Our Mileage Calculator helps you estimate fuel cost, MPG, cost per mile, and mileage reimbursement. All tools are completely free and require no account or registration.
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