Finance Calculators

Compare loans, mortgages, interest, investments, retirement, pay, tax and everyday money scenarios. This hub groups closely related tools so you can move from a broad question to the calculator that matches the exact job.

Each calculator opens with the working tool first, followed by the formula or method, a worked example, input guidance, common mistakes and related calculators. That keeps the category useful for quick calculations while still giving enough context to verify the result.

Calculator groups in this section

Loans & Housing

Payments, amortization, car finance and housing comparisons.

• Loan Calculator — Estimate monthly payment, total interest and total repayment.
• Auto Loan Calculator — Estimate a car loan payment after down payment and trade-in.
• Mortgage Calculator — Estimate monthly mortgage payment including optional taxes, insurance and HOA.
• Amortization Calculator — See monthly payment and the first-year principal/interest split.
• Rent vs Buy Calculator — Compare estimated housing cost of renting versus buying over time.

Saving & Investing

Interest, investments, inflation and deposit growth.

• Compound Interest Calculator — Project compound growth with optional regular contributions.
• Interest Calculator — Calculate simple interest and final balance.
• Investment Calculator — Project an investment balance with recurring contributions.
• Inflation Calculator — Estimate future equivalent cost using an assumed inflation rate.
• CD Calculator — Estimate certificate of deposit growth from APY and term.

Retirement

Long-term retirement, 401(k) and Roth IRA projections.

• Retirement Calculator — Project retirement savings from current balance and monthly contributions.
• 401(k) Calculator — Project a 401(k) including employee contributions and employer match.
• Roth IRA Calculator — Project a Roth IRA using a starting balance and yearly contributions.

Income & Tax

Pay, tax, salary and commission estimates.

• Tax Calculator — Calculate tax from an amount using a tax rate you provide.
• Sales Tax Calculator — Add or remove sales tax using a chosen rate.
• Paycheck Calculator — Estimate net pay from gross pay, withholding rate and deductions.
• Salary Calculator — Convert annual salary into monthly, weekly, daily and hourly equivalents.
• Commission Calculator — Calculate commission from sales and commission rate.
• Hourly to Salary Calculator — Convert an hourly wage to weekly, monthly and annual pay.

Everyday Money

Tips, margins, discounts, ROI and markup.

• Tip Calculator — Calculate tip, total bill and per-person split.
• Margin Calculator — Calculate gross profit, margin and markup from cost and selling price.
• Markup Calculator — Find selling price from cost and markup percentage.
• Discount Calculator — Calculate sale price and savings after a percentage discount.
• ROI Calculator — Calculate return on investment from cost and final value.

How to choose the right calculator

Start with the question you are trying to answer, not just the number you already have. A focused calculator usually gives clearer inputs and a more useful result than a general-purpose tool. If your problem changes units, formula type or planning goal, follow the related-calculator links instead of reusing a tool that was built for a different purpose.

Accuracy, assumptions and rounding

Simple mathematical and unit-conversion tools follow fixed relationships. Finance, health, construction, automotive and other planning calculators may also depend on assumptions you supply. Review the method on the individual calculator page, keep units consistent, and treat estimates as planning information rather than professional advice or a guaranteed real-world outcome.

See our calculator methodology for more detail about formulas, browser-based processing, units, rounding and update practices.