Finance Calculator X

Clear calculators for everyday financial decisions

Free calculators for loans, mortgages, investing, savings and debt — with documented formulas, worked examples, interactive charts, and downloadable tables or schedules where they add value.

LoanMortgageCompound InterestEMISIPDebt Payoff

Most used calculators

All calculators
Loan CalculatorMonthly payment, total interest and full amortization for any fixed-rate loan.LoansMortgage CalculatorTrue monthly payment including tax, insurance, PMI and HOA, plus amortization.MortgageCompound Interest CalculatorGrowth of a lump sum plus contributions, with any compounding frequency.InvestingEMI CalculatorMonthly EMI, total interest and prepayment savings on the reducing-balance method.LoansSIP CalculatorSIP maturity value with annual step-up and invested-vs-gains breakdown.InvestingDebt Payoff CalculatorMulti-debt payoff plan comparing snowball vs avalanche month by month.Personal FinanceHouse Affordability CalculatorHome price your income supports under 28/36 DTI rules, with the binding constraint named.MortgageRent vs Buy CalculatorNet cost of buying vs renting year by year, with break-even and equity at your horizon.Mortgage

Browse by category

Loan CalculatorsWork through payments, interest, repayment schedules and payoff options.10 calculators →Mortgage & Home CalculatorsEstimate home costs, affordability, refinancing and early payoff.8 calculators →Investment CalculatorsExplore compound growth, regular investing, future value and returns.8 calculators →Savings CalculatorsPlan regular deposits, savings goals and interest growth.2 calculators →Personal Finance CalculatorsBuild a workable budget and compare ways to repay debt.2 calculators →

What are you trying to do?

Buy a homeCompare two loan offersPay off debt fasterGrow my savingsStart investing monthlyPlan a big purchasePay off my mortgage earlyUnderstand a return

Decision & comparison tools

The most useful answers are comparisons: this loan or that one, extra payments or not, rent or buy. These tools put both options side by side.

Loan Comparison CalculatorTwo loan offers compared on payment, total cost, fees and effective APR.LoansRent vs Buy CalculatorNet cost of buying vs renting year by year, with break-even and equity at your horizon.MortgageExtra Payment CalculatorInterest saved and months cut by monthly, yearly or one-time prepayments.LoansRefinance CalculatorMonthly saving, break-even on fees, and lifetime cost of a refinance — term reset included.Mortgage

Trust & methodology

Numbers you can check

A calculator is only useful if you can trust it — so nothing here is a black box. Every calculator documents exactly how it works, and the full methodology is public.

How our calculations work
  • Every formula shown on the page, with variables explained
  • Automated tests verify results against known reference values
  • Assumptions and limitations stated on every calculator
  • Estimates for education — never personalized financial advice
  • Runs in your browser: normal calculator inputs are not submitted

Finance, explained properly

All guides
GuideAPR vs Interest Rate: What's the Difference?What APR includes that the interest rate doesn't, and a computed case where the lower rate loses.GuideDebt Snowball vs Debt AvalancheA computed four-debt case study of both payoff orders, plus when the avalanche edge is big or trivial.GuideHow Compound Interest WorksThe mechanism of interest-on-interest: frequency effects, the Rule of 72 tested, and time asymmetry.GuideHow EMI Is CalculatedThe EMI formula dissected, a ₹25 lakh loan computed by hand, and the flat-vs-reducing rate trap.

About Finance Calculator X

Finance Calculator X is an independent collection of financial calculators for the decisions most people actually face: borrowing, buying a home, saving, investing and paying off debt. Each calculator is built as a complete decision-support tool — a large, clear answer, the supporting numbers behind it, an interactive chart, a downloadable table or schedule where relevant, and a plain-English explanation of the mathematics involved. Calculations run instantly in your browser and are documented and tested. The site is free to use and no account is ever required. More about the project →