Personal Loan Calculator: Work Out Your Monthly Repayments

Run your numbers

Enter your loan amount, the representative APR you've been quoted (or one you want to test), and how many months or years you'd like to repay over. The personal loan calculator above gives you the monthly payment, the total amount repaid and the total interest in one go. Change any input and the figures update instantly, which makes it easy to compare a shorter term against a longer one.

What a personal loan actually is

A personal loan is a fixed sum of money you borrow from a bank, building society or lender and pay back in equal monthly instalments over an agreed period - typically one to seven years. Most high-street personal loans are unsecured, which means they aren't tied to your home or your car. The lender can't repossess an asset if you fall behind, but a missed payment still damages your credit file and can lead to court action for the debt.

The interest rate is usually fixed for the whole term, so your monthly payment stays the same from the first instalment to the last. That predictability is the main appeal: you know exactly what you owe each month and exactly when the loan ends. Borrowing tends to be cheapest in the middle of the range - lenders often reserve their lowest advertised rates for loans between roughly £7,500 and £15,000, with smaller and larger amounts carrying higher rates.

Secured vs unsecured: a quick but important distinction

An unsecured personal loan is what most people mean by "a loan" - no collateral, decision based on your income and credit history. A secured loan (sometimes called a homeowner loan or second-charge mortgage) is tied to your property. Secured borrowing can unlock larger sums and lower headline rates, but you're putting your home on the line. This calculator is built for unsecured personal loans, so if you're comparing a loan against your house, treat the output as a rough guide only and read the secured agreement carefully.

How the personal loan calculator works

Behind the scenes, a personal loan calculator uses the standard amortising loan formula. "Amortising" simply means each monthly payment covers the interest accrued that month first, with whatever is left chipping away at the balance you owe. Early on, more of your payment goes on interest; later, more goes on the capital.

The monthly payment is worked out like this, in plain words:

• Monthly payment = (Loan amount × monthly rate) ÷ (1 − (1 + monthly rate) raised to the power of minus the number of months)

The monthly rate is just the annual rate divided by 12. So a 9.9% APR becomes 0.825% a month (0.099 ÷ 12). The number of months is the term - a five-year loan is 60 months. Once you have the monthly payment, the rest is straightforward:

• Total repaid = monthly payment × number of months
• Total interest = total repaid − amount borrowed

One thing to keep in mind: lenders must quote a representative APR, which folds in compulsory fees as well as interest. At least 51% of accepted applicants must get that advertised rate or better, which means up to 49% can be offered something worse. The rate the calculator uses is whatever you type in, so for a realistic estimate use the actual rate in your loan offer, not the eye-catching figure in the advert.

Worked example: Priya borrows £10,000 for a kitchen

Priya wants to refit her kitchen and borrows £10,000 over five years (60 months) at a representative APR of 9.9%. Here's how the personal loan calculator gets to her monthly figure.

• Monthly rate: 9.9% ÷ 12 = 0.825%, or 0.00825 as a decimal
• Monthly payment: £10,000 × 0.00825 ÷ (1 − 1.00825 to the power of −60) = £211.98
• Total repaid: £211.98 × 60 = £12,718.72
• Total interest: £12,718.72 − £10,000 = £2,718.72

So Priya's £10,000 kitchen actually costs her £12,718.72 by the time the loan clears. That £2,718.72 of interest is the price of spreading the cost over five years rather than saving up.

The same loan over three years

If Priya could stretch to a higher monthly payment and chose a 36-month term at the same 9.9% rate, her monthly payment would rise but her total interest would fall sharply - because she's borrowing the money for a shorter time. This is the single most useful comparison the calculator offers: a longer term lowers the monthly payment but raises the total cost, while a shorter term does the opposite. Always look at both numbers, not just the monthly one.

A smaller, shorter loan

Take Daniel, who borrows £5,000 over three years (36 months) at 12.9% APR to cover an unexpected boiler replacement. His monthly payment works out at roughly £168.23, his total repaid is about £6,056.25, and his total interest is around £1,056.25. Smaller loans often carry higher rates, which is why his APR is steeper than Priya's even though he's borrowing half as much.

How much can you borrow on a personal loan?

UK personal loans typically range from £1,000 to £25,000, with some lenders going up to £50,000. How much you'll actually be offered depends on your income, your existing debts and your credit score - not just what you ask for. As a rough rule, lenders want your total monthly debt repayments to stay comfortably within your income, and they'll run an affordability check on your outgoings.

The calculator works the other way round too: if you know the monthly payment you can comfortably afford, try different loan amounts until the monthly figure matches your budget. That tells you a realistic borrowing target before you apply. Applying for far more than you can service is one of the quickest ways to get declined, and every hard credit search leaves a mark.

Personal loan vs credit card: which is cheaper?

For a one-off, planned purchase that you'll repay over a couple of years, a personal loan is usually cheaper than a standard credit card, because credit card interest tends to be higher and the minimum-payment structure can keep you in debt for years. A personal loan forces discipline: fixed payments, a fixed end date.

The exception is a 0% purchase or balance-transfer credit card. If you can clear the balance inside the interest-free window, a 0% card beats any loan because you pay no interest at all. The risk is the deal ending before you've cleared it, at which point the rate jumps. If you're juggling several debts, it's worth modelling both routes - our credit card repayment calculator shows how long a card balance really takes to clear, and the debt consolidation calculator compares rolling multiple debts into one loan.

How to get a better personal loan rate

The advertised APR isn't fixed in stone for you personally - several things you control can move it:

• Check your credit file first. Errors, an unregistered address or a missing electoral roll entry can drag your score down. Fixing them is free.
• Use eligibility checkers. Most lenders and comparison sites offer a soft search that shows your likely rate without leaving a hard footprint on your credit file.
• Borrow in the sweet spot. If you need £6,900, borrowing £7,500 can sometimes drop you into a lower rate tier - but only do this if the lower rate genuinely makes the larger loan cheaper overall. Run both through the calculator.
• Keep the term as short as you can afford. Every extra year adds interest. Aim for the shortest term where the monthly payment still leaves you breathing room.
• Don't apply scattergun. Several hard searches in a short space of time look like distress borrowing and can lower your score.

It's also worth checking the MoneyHelper guide to personal loans, a free and impartial service backed by government, before you commit.

Common mistakes people make

A few traps catch borrowers out time and again:

• Focusing only on the monthly payment. A low monthly figure usually means a long term and a lot more interest. Always check the total repaid.
• Assuming you'll get the representative APR. Up to 49% of accepted applicants are offered a higher rate. Treat the advertised figure as a best case, then recalculate with your actual offer.
• Ignoring early-repayment charges. Many personal loans let you overpay or settle early, but some charge up to roughly two months' interest as an early settlement fee. If you might repay early, factor that in - our early repayment calculator can help you weigh it up.
• Confusing APR with a flat rate. Some car and retail finance advertises a "flat rate" that looks low but is calculated on the original balance throughout. APR reflects the true cost on the reducing balance and is the only fair way to compare.
• Borrowing to cover everyday spending. A personal loan suits a planned, one-off cost. Using one to plug a recurring shortfall in your budget usually deepens the problem rather than solving it.

Should you take the loan at all?

Before you borrow, it's worth a moment of honesty about whether the purchase can wait. If you could save the amount within a year, the interest you'd avoid often outweighs the wait. If the spending is genuinely urgent or unavoidable - a broken boiler in January, say - then a fixed-rate personal loan is one of the more transparent ways to spread the cost, far cleaner than rolling debt around credit cards. The calculator gives you the numbers; the decision is whether that monthly commitment fits your life for the whole term, not just today.

For a broader view of repayment options across loan types, our general loan calculator and loan repayment calculator let you model different structures side by side.

These figures are estimates for guidance only and are not personal financial or debt advice. Your actual rate, fees and eligibility depend on the lender and your circumstances - always check your loan agreement before signing.

The advertised rate isn't always what you'll get. Our guide to personal loans and APR explains how to compare the real cost.

The numbers: what a £10,000 loan really costs

Monthly repayments and the total cost of borrowing £10,000 at typical UK personal loan APRs. Scale to your amount.

Lenders must show the APR including fees. Free debt and borrowing guidance: MoneyHelper.

Who should use this calculator

This is for comparing unsecured personal loan offers before you commit. The useful discipline is to hold the amount steady and vary the term: the monthly payment falls as you stretch it, the total interest rises, and seeing both at once is what stops a “more affordable” loan quietly costing far more.

Where it differs from the general loan calculator is emphasis on the representative APR trap. Advertised rates only have to be offered to 51% of accepted applicants, so almost half of successful borrowers are given something worse than the headline — and you often do not find out until after a credit check.

What this calculator assumes

• A fixed-rate, fixed-term unsecured loan with equal monthly repayments, which is standard for UK personal loans.
• The rate entered is the actual rate you are offered, not necessarily the advertised representative APR.
• Interest accrues on the reducing balance.
• No fees are added to the advance.

Limitations — what it does not cover

• The gap between representative and offered APR, which depends entirely on your credit file.
• Early settlement interest — up to around 58 days’ interest may be charged under the Consumer Credit Act.
• The credit-search effect of applying; use eligibility checkers that perform a soft search first.
• Optional insurance added at the point of sale.
• Alternatives — a 0% purchase card or an authorised overdraft can be cheaper for smaller sums over shorter periods.