Best Free Online Finance Calculators
Money questions almost always reduce to one number: the monthly payment, the final balance, the real sale price. This collection gathers the nine finance calculators people reach for most — mortgage with tax/insurance/HOA, loan payoff dates, ad ROI, rent budgets, bill splitting and more.
Every result shows the formula behind it. Estimates are for planning only — your lender’s figures govern.
Mortgage Calculator
P&I plus tax/ins/HOA, extra-payment payoff, amortization.
Loan Calculator
Payment, total interest and payoff date for any loan.
Tip Calculator
Tip presets, per-person split and round-up.
Compound Interest Calculator
Growth chart vs simple interest, any compounding.
Discount Calculator
Percent-off, zhe discounts and stacked discounts.
Percentage Calculator
All four percent problems, formulas shown.
ROI Calculator
Orders, revenue, profit, ROI and breakeven for ad spend.
Financial Calculator
Compound, SIP and goal-backward calculators in one.
Rent Cost Calculator
Move-in cost, lease total and true monthly rent.
Retirement Calculator
Nest-egg target, projected balance and gap.