Calculateur de Compound Interest
Calculate future value with compound interest and monthly contributions.
Formula and method
This calculator computes Future value, Contributions directly in your browser without sending data to an external server.
Mathematical formula
- Future value:
(() => { const r=rate ÷ 1200; const n=years × 12; if (r===0) return principal + monthly × n; const pow=1+r^(n); return Number.isFinite(pow) ? principal × pow + monthly × ((pow-1) ÷ r) : NaN; })() - Contributions:
principal + monthly × years × 12
Variables and parameters
- Starting amount (principal): default value 10000 $.
- Monthly contribution (monthly): default value 250 $.
- Annual return (rate): default value 7 %.
- Years (years): default value 20.
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 Compound Interest Calculator use?
Compound Interest Calculator evaluates outputs such as <strong>Future value, Contributions</strong> based on inputs including Starting amount, Monthly contribution, Annual return, Years. Check the Mathematical Method section for the explicit formula.
How can I compare different financial scenarios using Compound Interest 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 Compound Interest 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 Compound Interest 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 Compound Interest Calculator free to use?
Yes. Compound Interest Calculator is completely free, has no usage limit, and does not require an account, email, or API key.
Does Compound Interest Calculator store or upload my data?
No. Compound Interest Calculator calculates everything locally in your browser. Nothing you type is sent to a server or stored by SpecWhale.
How accurate is Compound Interest Calculator?
Compound Interest 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 Compound Interest Calculator on my own website?
Yes. Use the "Embed this tool" snippet on this page to add a free, working copy of Compound Interest Calculator to your own blog post or page.