How this calculator works
One question, asked properly: what does owning cost you that renting doesn't, and is the equity you build worth more than what that costs? Everything below is the bookkeeping that answers it — and where the model is honest about its limits.
The method
The whole tool answers one question: how much richer are you after X years if you buy, versus if you rent? Everything else is just the bookkeeping to get there honestly.
The buyer's wealth is what they could walk away with — the home's market value, minus the mortgage still owed and the cost of selling. The renter's wealth is their investment portfolio. To keep it fair, the renter invests everything the buyer ties up in the property: the deposit and all the costs at the notary on day one, and thereafter, in any month where renting is cheaper, the monthly saving too. In Amsterdam owning is often the cheaper option month to month, so more often than not it's the buyer with money left over to invest — and the model gives that surplus back to the buyer's side rather than pretending it vanishes.
At your chosen horizon both sides are tallied and compared. Breakeven is the first month the buyer comes out ahead.
Interest is taken from the real amortisation schedule, month by month on the declining balance — not an average. With an annuity the payment is level but its composition shifts continuously: early on it's mostly interest, later mostly principal. That matters twice over. Your deductible interest falls every month while the eigenwoningforfait rises with the house, so the tax relief shrinks from both ends. And a short holding period is far more interest-heavy than the headline rate suggests — which is a big part of why buying rarely wins over a two or three year horizon.
A mortgage payment is not a cost. The part that repays principal becomes equity — it moved, it wasn't spent. Only interest, fees, taxes and upkeep are actually burned. That's why the calculator shows "net cost of housing" rather than total outgoings.
Nominal vs today's euros
In the calculator, the toggle in the top corner switches every figure between nominal and today's euros. Nominal (the default) is the raw number of euros that actually changes hands in the future. Today's euros — also called real terms — discount those future amounts back by inflation, because a euro in 10 years buys less than a euro now.
It is purely a lens on the same simulation: it rescales what you see but never changes who wins or which month you break even. At 2,0% inflation over a 10-year horizon, a euro in the future is worth about 18% less in today's money — so flip between the two to see how much of the headline gap is real gain and how much is just inflation puffing up the numbers.
One-off costs of buying
Financing costs are deductible in full in year one, not spread. Purchase costs never are. The model applies that split correctly.
Recurring costs of owning
Tax
Deliberately excluded
The comparison only counts what differs. Anything both a renter and an owner pay would cancel out, so including it just makes the numbers bigger without changing the answer:
Where the model is wrong
It's a straight line. Returns and prices compound smoothly. Reality is lumpy, and a bad sequence hurts a 90%-leveraged owner far more than the average suggests.
The rate never changes. No refinancing, no reset at the end of your fixed period, no early repayment.
Relief is capped at a flat 37,56%. Right for anyone earning above €78.426. Below that your actual bracket applies — edit the field.
Interest relief is assumed to survive. It has been politically live since 2025. If buying only wins with it switched on, that's worth knowing, so switch it off and look.
Nothing here is priced for the things that aren't money — a landlord ending your contract, being unable to move for work, or the freedom to knock down a wall.