Finance guides
Read DigiCalc's finance guides and explore related calculators. Page 3 of 4.
How Does a Mortgage Amortization Schedule Work?
Read principal, interest and annual balance rows, with tested mortgage examples and recurring extra-payment comparisons from the calculator engine.
FinanceHow Inflation Affects the Value of Money Over Time
Compare published U.S. annual CPI values from 1913-2025, reverse purchasing-power calculations and exact real-return arithmetic.
FinanceHow to Calculate Return on Investment (ROI) Step by Step
Learn how to calculate return on investment (ROI) with the exact formula, step-by-step examples for stocks and real estate, and what counts as a good ROI.
FinanceHow Much Car Can I Afford? The 20/4/10 Rule Explained
Find out how much car you can afford using the 20/4/10 rule, monthly payment math, and true ownership costs — with real examples for different incomes.
FinanceHow to Pay Off a Loan Faster (and How Much You Save)
Compare recurring extra payments and an up-front lump sum against your actual monthly payment, with tested examples and explicit timing assumptions.
FinanceIs Buying an Electric Car Worth It? The Real Math
Compare EV energy and ownership costs with explicit assumptions, no assumed purchase rebate, and the US federal credit acquisition cutoff.
FinanceIs It Worth Refinancing Your Mortgage? The Break-Even Math
Find out if refinancing your mortgage makes financial sense. Calculate your break-even point, monthly savings, and total interest saved — with real examples.
FinanceIs It Cheaper to Rent or Buy a House? The Real Math
Compare rent and ownership with equal budgets, separate investment earnings from contributions, and understand the first buying advantage.
FinanceHow Compound Interest Grows Your Savings: Worked Examples
Compare a one-time deposit, monthly contributions and compounding frequency using reproducible examples, clear assumptions and a free calculator.