Free calculators · private · no signup
Get a clear answer to a money question without creating an account. Koody's free calculators show the assumptions, explain the math, and run entirely in your browser.
Estimate 2026 US take-home pay with automatic federal and state withholding, Social Security, Medicare, and applicable employee payroll programs.
Project a workplace retirement balance with employee contributions, employer match, fees, and 2026 contribution limits.
Compare projected savings with an editable retirement-income goal, then estimate how much more you may need to save each month.
See how an initial balance, regular contributions, withdrawals, and compounding can change your savings over time.
Estimate your 2026 Roth IRA contribution limit, then project contributions and investment growth through retirement.
Estimate your financial independence number, see when you could reach it, and test contribution and withdrawal-rate scenarios.
Calculate gratuity before or after tax, account for an existing service charge, and split the final bill.
Start with the question
Use the 401(k) calculator to include an employer match, or check current eligibility with the Roth IRA calculator.
Find a financial-independence target with the FIRE number calculator, then test a retirement-income goal with the retirement calculator.
Project savings with the compound interest calculator, or calculate and split a restaurant bill with the tip calculator.
Use the paycheck calculator to estimate 2026 federal and automatic state withholding, FICA, employee payroll programs, and verified local rules where available.
Behind the numbers
These are educational tools for exploring scenarios, not forecasts, guarantees, or personal financial advice.
Each calculator explains its formula, timing rules, and worked example.
Defaults are starting points. Rates, timing, inflation, and other assumptions stay visible and editable.
Raw calculator inputs stay in this browser. They are not saved or sent to Koody.
You do not need an account, a bank connection, cookies, geolocation, or a third-party calculator.