What Finzcore is
Finzcore is a small, independent site with one job: helping you understand the money decisions in front of you. We do that with two things — free calculators (mortgages, retirement, compound interest, debt payoff, budgeting and more) and jargon-free guides about budgeting, saving, debt and investing.
Everything here is free, requires no account, and shows no results behind a paywall. There is nothing to install and nothing to sign up for.
How the calculators work
Every tool uses the standard, textbook financial formulas — the same math a bank or a spreadsheet would use:
- Compound interest and savings goals use periodic compounding with contributions treated as an ordinary annuity; the savings goal tool solves the same equation for the payment.
- Loans and mortgages are amortized with either a fixed payment (the annuity formula) or fixed principal, at the nominal annual rate divided by twelve. The mortgage tool adds property tax, insurance, PMI and HOA, and drops PMI when the balance reaches 80% of the home's value.
- Debt payoff and credit cards run month-by-month simulations, accruing interest on each balance — snowball versus avalanche for multiple debts, minimum payment versus a fixed payment for a single card.
- Retirement projects the accumulation phase nominally, then draws the balance down in real terms using a return net of inflation, so every figure is shown in today's money.
- Inflation compounds an assumed average rate you control rather than a historical price index — useful for planning ahead, and clearly labelled as an estimate.
- The 50/30/20 budget follows the rule popularised by US senator Elizabeth Warren, applied to after-tax income.
- Debt-to-income, net worth, emergency fund and salary conversion use the same definitions lenders and planners use, with every threshold and assumption written out on the page.
The formulas are documented in plain English on each calculator page, so you can check our work.
Your numbers stay yours
The calculators run entirely inside your browser. The figures you type — your income, your debts, your savings — are never sent to our servers, never stored, and never shared. We couldn't sell your financial data even if we wanted to, because we never receive it.
The only personal data we ever hold is your email address, and only if you choose to subscribe to the newsletter. You can unsubscribe at any time. See the privacy policy for details.
What we are not
Finzcore is educational, not advisory. We are not a bank, a broker or a licensed financial adviser, and nothing on this site is personalised financial, legal, tax or investment advice. Results are estimates: your bank may add fees, insurance or rounding that change the final figures. For decisions that matter, consult a licensed professional in your country.
How we keep it accurate
Calculators are tested against independent implementations of the same formulas before they ship, and every page shows its last update date. If you spot an error — in a calculation, a guide or anything else — please tell us and we will fix it.
Contact
Questions, corrections or suggestions: finzcore@proton.me. We usually reply within 24–48 hours on working days.