Calculateur de Debt Payoff
Estimate months to pay off a debt with a fixed monthly payment and interest rate.
Formula and method
This calculator computes Months to payoff (approx.) directly in your browser without sending data to an external server.
Mathematical formula
- Months to payoff (approx.):
(() => { const r=rate ÷ 1200; return r===0 ? balance ÷ payment : (payment<=balance × r ? NaN : -Math.log(1-(balance × r) ÷ payment) ÷ Math.log(1+r)); })()
Variables and parameters
- Balance (balance): default value 5000.
- Annual interest rate (rate): default value 20 %.
- Monthly payment (payment): default value 200.
Some formulas are undefined for certain input combinations (such as division by zero or logarithms of non-positive numbers). In those cases the live tool displays an alert instead of NaN.
Embed this tool
Paste this snippet into your own site or blog post to embed a live, working copy of this tool. It links back to the full page on SpecWhale.
Frequently asked questions
What equation and variables does Debt Payoff Calculator use?
Debt Payoff Calculator evaluates outputs such as <strong>Months to payoff (approx.)</strong> based on inputs including Balance, Annual interest rate, Monthly payment. Check the Mathematical Method section for the explicit formula.
How can I compare different financial scenarios using Debt Payoff Calculator?
You can click the "Add to Compare" button after computing your scenario to pin it to your temporary side-by-side Compare Workbench, allowing you to evaluate loan, rate, or interest differences.
What happens if I enter invalid or zero values into Debt Payoff Calculator?
If an input combination is mathematically undefined (such as division by zero or negative square roots), SpecWhale alerts you gracefully rather than returning invalid NaN outputs.
Are my calculations in Debt Payoff Calculator saved or private?
All calculations are 100% private and run locally in your Web browser. Your numbers are never uploaded to any server, but can be saved locally to your device or exported as CSV/JSON.
Is Debt Payoff Calculator free to use?
Yes. Debt Payoff Calculator is completely free, has no usage limit, and does not require an account, email, or API key.
Does Debt Payoff Calculator store or upload my data?
No. Debt Payoff Calculator calculates everything locally in your browser. Nothing you type is sent to a server or stored by SpecWhale.
How accurate is Debt Payoff Calculator?
Debt Payoff Calculator uses a standard formula (see the Method section above for the exact expression). For high-stakes financial, medical, or legal decisions, confirm the result with a professional or an authoritative source before relying on it.
Can I embed Debt Payoff Calculator on my own website?
Yes. Use the "Embed this tool" snippet on this page to add a free, working copy of Debt Payoff Calculator to your own blog post or page.