Mortgage guides worth reading first
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Mortgage Terms Explained: The Words on Every Offer
APR, LTV, DTI, amortisation, early repayment charge, porting — the vocabulary you need before comparing two offers, with what each one actually costs you.
How a Mortgage Actually Works, Start to Finish
What you are agreeing to when you take a mortgage: the security, the stages of the process, and the points where the deal can still change.
How a Mortgage Calculator Works: The Formula, Shown
One equation produces the monthly payment, and everything else follows from running it month by month. Here is the arithmetic, and what most calculators leave out.
Debt to Income: The Ratio That Decides More Applications Than Salary
How DTI is calculated, what counts as debt, the caps that apply in different markets, and the fastest ways to move the ratio before applying.
Deposit and LTV: Why the Bands Matter More Than the Amount
Rates are priced in LTV bands, so a small extra deposit that crosses a threshold can be worth more than any negotiation. Here is where the thresholds sit.
Rates, costs and the type of loan
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How Mortgage Interest Is Calculated, Month by Month
Interest is charged on what you still owe, not on what you borrowed. That one sentence explains amortisation, overpayment savings and daily interest.
APR and Fees: Why the Cheapest Rate Is Often the Expensive Deal
A large arrangement fee can turn the best headline rate into the worst offer. Here is how APR works, what it misses, and how to compare properly.
Fixed or Variable? The Decision Is About Your Budget, Not the Market
Fixed buys certainty and costs a little more; variable starts lower and moves. The honest test is what a three-point rise would do to you.
First-Time Buyer Mortgages: The Schemes, and the Catches
Low-deposit products, state guarantees and shared ownership all reduce the cash you need — and each of them costs something. Here is what.
Mortgage calculators by country
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Rate explainers, affordability rules, deposit and LTV, and what actually changes when you overpay or refinance.
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Why read us first
- Every guide is written and reviewed in house, and carries the date of its last review.
- The calculator runs entirely in your browser — no income or price figure is ever transmitted or stored.
- Each market page uses that country’s own currency, rate convention, deposit rule and purchase taxes rather than an American default.
- Purchase costs are itemised as a percentage of the price, so you can see which line is the large one.
- Every guide exists in twelve languages with its own URL, not a machine pop-up.
- Nothing is behind a signup: no email wall, no locked chapters, no upsell.
Frequently asked questions
How does a mortgage calculator work?
It solves one equation. For a standard repayment loan the monthly payment is the amount borrowed multiplied by the monthly interest rate, divided by one minus (one plus the monthly rate) raised to minus the number of months. That single formula produces a payment which, repeated for the whole term, clears the debt exactly. Everything else a good calculator shows — total interest, the balance after five years, how much of the first payment is interest — comes from running that payment through the balance month by month. Ours also adds the purchase costs, because those decide whether you can complete at all.
Why is my mortgage calculation different from the bank’s?
Usually for one of four reasons. The bank is quoting APR rather than the nominal rate, so its figure includes fees. It is adding compulsory insurance to the payment. It is using a slightly different day-count or rounding convention. Or the rate it has offered you is not the one you typed in, because your deposit, income or credit history put you in a different band. A calculator gives you the shape of the deal; only a lender’s illustration gives you the deal.
How much deposit do I need?
It depends entirely on the market, which is why this site has a page per country. Around a fifth of the price is the common expectation in Germany, Spain and Italy, and it also removes mortgage insurance in the United States. Ten per cent is workable in the United Kingdom and Portugal. The Netherlands still allows borrowing the full purchase price. But there is a second question that matters as much: purchase taxes and fees are almost never lendable, so in a market where they run to a tenth of the price you need that in cash on top of the deposit.
Should I take a fixed or a variable rate?
It is a question about your budget rather than about forecasting rates. A fixed rate buys certainty and normally costs slightly more at the outset; a variable rate starts lower and moves. The honest test is what happens to you if the payment rises by two or three percentage points: if that would be uncomfortable rather than merely annoying, the certainty is worth paying for. Note that the two words mean different things by country — a British five-year fix is a short window inside a long term, while a French or Dutch fix can run the whole way.
Is it better to shorten the term or to overpay?
They achieve almost the same thing with a very different risk profile. A shorter term forces higher payments and locks you into them. Overpaying a longer-term loan produces nearly the same saving while leaving you the option of stopping in a difficult month. For most people the flexible version is the better arrangement, provided you actually make the overpayments. Two things to check first: whether your lender charges an early repayment fee, and whether the overpayment reduces the term or the monthly payment, because the saving is much larger when it reduces the term.
Does this calculator store what I type?
No. The whole calculation runs in your browser using JavaScript on the page. The price, deposit, rate and term you enter are never sent to a server, never logged and never stored, because there is no request to send them in — there is no reason for arithmetic to leave your device, and refusing to collect the data is the only privacy promise that cannot be broken later.