Mortgage simulator
Compute your monthly payment, the total cost of your mortgage, and see the principal / interest / insurance split. Yearly amortization schedule included, no sign-up.
Loan parameters
Calculated on the initial capital (most common method).
Indicative simulation, not legally binding. Reach out to a lender or broker for a personalized offer.
Estimated monthly payment
Cost breakdown
In plain words
For borrowed, you will repay a total of . The loan therefore raises your project cost by .
Amortization schedule (yearly)
| Year | Total payment | Principal paid | Interest paid | Remaining balance |
|---|---|---|---|---|
Go deeper
Why simulate your mortgage before signing?
A mortgage typically commits you for 15, 20 or 25 years. Before signing any preliminary credit offer, you must know precisely your monthly payment and the total cost of your loan. Our simulator instantly estimates the payment and lets you compare multiple scenarios: rate, duration, down payment, insurance.
The monthly payment formula
M = [ P × (r/12) ] / [ 1 − (1 + (r/12))−n ]
- M — the monthly payment (excluding insurance)
- P — the borrowed principal
- r — the nominal annual interest rate
- n — the total number of monthly installments
Each month, the bank computes interest on the remaining balance. That's why early on you mostly repay interest; near the end, almost only principal. The built-in amortization schedule shows this mechanic year after year.
3 levers to reduce the cost of your loan
More down payment
Reducing the principal mechanically cuts interest. An extra 10% saves thousands.
Shorter duration
Going from 25 to 20 years raises the monthly payment but can roughly halve total interest.
External insurance
You're not forced to take the bank's insurance. Switching often saves €5,000 to €15,000.
The 35% debt-to-income threshold
In France, the HCSF caps the debt-to-income ratio at 35% of net income, insurance included. In practice:
- €3,000 net income → max payment ≈ €1,050.
- €4,500 net income → max payment ≈ €1,575.
- €6,000 net income → max payment ≈ €2,100.
Exceptions exist (first-time buyers, large assets), but they remain rare.
Simulator features
- Live calculation: every change updates the payment, total cost and chart in real time.
- Visual donut: principal / interest / insurance / fees split at a glance.
- Yearly amortization table: see the remaining balance year after year.
- Shareable link: your inputs are stored in the URL to share the exact same simulation.
FAQ
Does the calculation include mortgage insurance?
By default no — the monthly payment is shown excluding insurance. By checking "Include insurance", you can enter an annual rate (typically 0.10% to 0.50%) added to the payment. Insurance is calculated on the initial capital, the most common method in France.
Is this simulation 100% accurate?
It's a precise mathematical estimate using the standard fixed-rate loan formula. However, each bank applies its own rounding rules and value-day handling. The official amortization schedule will be your bank's, which can vary by a few euros per month.
Where should I enter notary fees?
Generally, notary fees are paid through your down payment, not integrated in the loan. If you choose to finance them, simply add the amount to the "Loan amount" field. The "Fees" field is for bank fees (around 0.5–1% of the principal).
Why do we repay more interest at the beginning?
Because interest is computed on the remaining balance. Early on, that balance is at its maximum, so the interest share of the payment is high. As you repay, the balance shrinks and so does the interest share. The built-in yearly amortization table shows this declining curve.
Should my debt-to-income ratio stay below 35%?
It's the rule set in France by the HCSF since 2022: the total monthly payment (insurance included) must not exceed 35% of your net income. A few exceptions exist (first-time buyers, asset-based files), but they apply to less than 20% of loans. Aiming for 30% leaves you breathing room.
Can I share my simulation with someone?
Yes. The "Share link" button copies the URL with all your parameters encoded in it. Whoever opens the link lands on the same simulation, ready to tweak. No data is stored server-side.
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