How this loan calculator works
This calculator runs the standard annuity loan formula — a fixed monthly payment that combines principal and interest, with the split shifting over time. In the early months, most of your payment goes to interest because the outstanding balance is high. As the balance shrinks, more of each payment goes to principal. By the final months you're paying almost entirely principal with very little interest.
The optional "extra monthly payment" field shows what happens when you pay above the required minimum. Even small extras dramatically reduce both the total interest paid and the months until you're debt-free, because every euro of extra principal directly shrinks the balance that gets charged interest the following month.
The formula being used
The monthly payment M on a loan of principal P at monthly interest rate r over n total months is:
M = P × [r × (1+r)n] / [(1+r)n − 1]
The monthly rate r is the annual rate divided by 12. The term n is years multiplied by 12. From there, each month: interest portion = balance × r, principal portion = M − interest portion, new balance = old balance − principal portion.
Should you take this loan?
The calculator tells you what a loan costs. Whether it's a good idea is a separate question. Three quick checks before signing:
1. The 10% rule
A common guideline: total monthly debt payments (all loans, including a mortgage) should stay under 36% of your gross income, and non-mortgage debt should stay under 10–15%. If a €350/month loan payment pushes you above that, the loan is probably too big or the term too short for your current finances.
2. The total cost question
Always look at total cost, not just the monthly payment. A €15,000 loan at 6.5% over 5 years costs roughly €17,650 total — €2,650 of pure interest. Stretch the same loan to 10 years and the monthly drops to ~€170, which feels cheaper — but the total cost rises to around €20,400, almost €3,000 more in interest. The longer the term, the lower the monthly, but the higher the lifetime cost.
3. The opportunity cost
If you have savings sitting in a low-yield account and are about to take a 7% loan, you're effectively choosing to earn 2% on your savings while paying 7% on borrowed money. Almost always better to pay cash for the smaller purchase first. The exception: when the loan is for an appreciating or income-producing asset (a property, a business, education), and the expected return on that asset exceeds the loan's interest rate.
APR vs. nominal rate — the number you actually care about
Lenders quote two different "rates" and it matters which one you compare:
- Nominal interest rate — the headline rate used in the monthly-payment formula. This is what most consumer loans advertise.
- APR (annual percentage rate) — the rate that includes all fees: origination fees, processing fees, mandatory insurance, broker fees. In the EU this is called the JKP (jaarlijks kostenpercentage) and lenders are legally required to disclose it.
The APR is the only number that lets you compare two loans fairly. A loan with a 5.9% nominal rate and €600 in fees can have a higher real cost than a loan with a 6.3% rate and zero fees. Always ask for and compare APRs, not nominal rates.
The mathematics of early repayment
Paying extra on a loan is one of the highest-return moves available in personal finance, because the "return" equals your loan's interest rate — and that rate is usually higher than what you'd earn investing the same money elsewhere.
An example: on a €15,000 loan at 6.5% over 5 years, the required monthly payment is about €293. Adding just €50/month extra finishes the loan in roughly 4 years instead of 5, and saves around €380 in interest. Adding €100/month extra finishes it in 3.5 years and saves around €640. The savings compound with every extra euro because each one prevents interest from being charged on the next month's balance.
Try this in the calculator: set "Extra monthly payment" to €50 or €100 and watch how the total interest column shrinks. The same euro spent on extra principal is far more powerful in the first half of the loan than the second half, because there's more balance left to charge interest against.
That said, before throwing all extra cash at a loan, also consider what that money could earn elsewhere. If the loan rate is 4% and you can reliably earn 7% in a long-term investment, the math favours investing — though the certainty of debt payoff has a real psychological value that the math doesn't capture. Our compound interest calculator lets you model what the same euro would grow to if invested instead.
Common loan types and what to watch for
Personal loans
Unsecured (no collateral), typically €1,000–€50,000, terms of 1–7 years, EU rates currently in the 5–12% range. Used for renovations, weddings, emergencies, debt consolidation. Watch out for: high APRs at smaller amounts, prepayment penalties, mandatory insurance add-ons.
Car loans
Often secured against the car itself, which makes rates a bit lower (4–8% range in the EU). Terms of 3–7 years. Watch out for: dealership financing that bundles a low rate with a high price; balloon-payment structures that leave a large lump sum at the end.
Student loans
Government-backed programmes (DUO in NL, BAföG in DE, student finance in the UK) have far better terms than private equivalents — lower rates, longer terms, often income-contingent repayment. Almost always exhaust government options before considering private student loans.
Debt consolidation loans
Combining multiple debts (credit cards, store cards, small loans) into one larger loan at a single lower rate. Can dramatically reduce total interest if you don't run up the original cards again. The biggest risk is treating the cleared cards as fresh credit and ending up with the consolidation loan plus new card balances.
Mortgages
Loans secured against property, with their own specific dynamics — much larger amounts, much longer terms, and often different tax treatment. Our dedicated mortgage calculator handles property price, down payment, LTV, and fixed-rate periods properly.
Common mistakes when taking a loan
Optimising only for the monthly payment
The single biggest mistake. A longer term always means a lower monthly, but a higher total cost. If you're choosing between a 5-year and 7-year term, the 5-year almost always wins on lifetime cost — only take the longer term if the 5-year monthly is genuinely unaffordable.
Skipping the prepayment-penalty check
Some lenders charge a fee if you pay the loan off early. In the EU this is regulated (capped at 1% of the amount being repaid early, or 0.5% if there's less than a year left), but it's still worth confirming. A loan with a prepayment penalty makes the early-repayment math less attractive.
Not reading the variable-rate clauses
Some loans advertise a low initial rate that converts to a variable rate after 1–2 years. The headline number is misleading. Always ask: what's the maximum rate this loan can charge if all variable-rate triggers kick in?
Frequently asked questions
Does this calculator include APR or just the nominal rate?
The calculator uses whatever rate you enter. To get the most realistic monthly payment, enter the APR (the EU-required total cost percentage including all fees) rather than the nominal rate. If you only have the nominal rate plus a list of fees, add the fees to the loan amount as a rough approximation — the resulting monthly will be close to the APR-based figure.
What's a "good" interest rate right now?
Rates change with the central bank base rate, but as a rough guide for EU consumer loans in 2026: a credit-worthy borrower can expect 5–7% for personal loans, 4–6% for secured car loans, and 3–5% for government-backed student loans. Anything above 12% on a personal loan is expensive and worth shopping around.
Should I take a longer term to keep monthly payments low?
Only if the shorter-term monthly is genuinely unaffordable. Every extra year of term adds significant interest. A 10-year loan typically costs 60–80% more in total interest than the same loan at 5 years. If you can afford the shorter term, take it. If you can't, take the longer term but try to overpay when cash flow allows — it's the same effect as a shorter term but with flexibility.
How does extra monthly payment compare to a one-off lump sum?
A €5,000 lump sum applied in month 12 saves more interest than €100/month extra over the full term, because the lump sum kills the balance earlier. But the €100/month is easier to sustain, doesn't require a windfall, and starts saving interest immediately. Both are good — the best strategy if you have both windfall money and steady savings is to do both.
Should I save in parallel or focus all cash on the loan?
Always maintain a small emergency fund (at least 1 month of expenses) alongside aggressive debt payoff. Without it, the first unexpected expense forces you to take a new loan, undoing your progress. After that buffer is in place, focus on whichever has the higher "rate" — usually the debt, unless you have access to employer-matched retirement contributions, in which case grab those first since the match is effectively a 100% return.