Personal finance calculators for clearer scenarios
Personal Finance Calculators
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FinKit is a set of free, client-side calculators for loans, savings, and everyday money math. Enter numbers, apply standard formulas, and compare scenarios without creating an account or connecting a bank.
Use amortization and payment tools when you want to see how interest and principal split over time. Check debt-to-income or refinance break-even before you talk to a lender. Everyday helpers cover tips, percentages, and APY estimates. Results are educational only — not personalized financial advice, quotes, or offers.
Every calculator page includes a short how-to, FAQ, and a clear disclaimer. Guides expand the ideas behind the formulas — what amortization means, how DTI is used in underwriting conversations, and why APY and APR answer different questions — without telling you which product to buy.
Featured in this kit
Amortization Schedule Calculator
Build a month-by-month loan payoff table with principal and interest splits.
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- Amortization Schedule Calculator
Build a month-by-month loan payoff table with principal and interest splits.
- Debt-to-Income Ratio Calculator
Measure monthly debt payments against gross income for mortgage readiness.
- Refinance Break-Even Calculator
Estimate how long refinancing savings take to recover closing costs.
- APY Calculator
Convert APR to annual percentage yield based on compounding frequency.
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Loans
Amortization Schedule Calculator
Build a month-by-month loan payoff table with principal and interest splits.
Debt-to-Income Ratio Calculator
Measure monthly debt payments against gross income for mortgage readiness.
Refinance Break-Even Calculator
Estimate how long refinancing savings take to recover closing costs.
Auto Loan Payment Calculator
Estimate a fixed monthly car loan payment from amount, rate, and term.
Personal Loan Payment Calculator
Project installment payments for unsecured personal loans.
Guides
Short explainers for the ideas behind the calculators — amortization, DTI, APY vs APR, and everyday percentage math — written for learning, not for recommending a specific loan or investment.
- How Loan Amortization Works (Plain English)
Understand why early loan payments are interest-heavy and how an amortization schedule helps you compare offers.
- What Is Debt-to-Income (DTI) Ratio?
How lenders use DTI, what to include in the calculation, and why gross income is the usual baseline.
- Mortgage Payment Basics: PITI and Principal vs Interest
What makes up a typical monthly housing payment, how fixed-rate amortization fits in, and what calculators leave out.
- APY vs APR: What's the Difference?
How annual percentage yield and annual percentage rate describe returns and borrowing costs differently — and why the higher number is not always 'better'.
- Tip and Percentage Basics: Split Bills Fairly
How to calculate tips, pre-tax vs post-tax etiquette, and split checks without rounding arguments — math only, not spending advice.
- How to Read a Loan Payment Estimate
What principal, interest, term, and monthly payment mean together — educational framing before you talk to a lender.
- Refinance Break-Even: What the Math Is Asking
How to think about closing costs versus monthly savings when exploring a refinance — educational only, not a recommendation.
Educational estimate only. Not financial advice.