Money math, made visual.
Free interactive calculators that show you what your money can do — compounding, early retirement, debt payoff, and the big "what if" decisions. No signup. No fees. Just clear math, explained in plain English.
Pick a calculator
Every tool recalculates live as you type, draws you a chart, and explains the math behind the answer.
Compound Interest Calculator
See how your savings grow when returns earn their own returns — with a year-by-year breakdown.
Open calculator →FIRE Calculator
Financial Independence, Retire Early: how many years until your investments can cover your spending?
Open calculator →Coast FIRE Calculator
Find the age when you can stop saving for retirement and let compounding finish the job.
Open calculator →Retirement & 4% Rule Calculator
Project your nest egg, then estimate a sustainable annual withdrawal using the famous 4% guideline.
Open calculator →Debt Payoff Calculator
Avalanche vs. snowball, side by side: which strategy gets you debt-free faster and cheaper?
Open calculator →Mortgage vs. Invest Calculator
Extra cash each month: prepay the mortgage or invest it? Compare interest saved vs. investment growth.
Open calculator →SIP Calculator
Systematic Investment Plan: see what a fixed monthly investment grows into — the same math as dollar-cost averaging.
Open calculator →HSA Calculator
The triple tax advantage, quantified: compare an HSA head-to-head with a taxable brokerage account.
Open calculator →Take-Home Pay Calculator
2026 brackets: what your salary actually becomes after federal tax and FICA.
Open calculator →Roth vs Traditional Calculator
Pay tax now or later? Compare after-tax values and get a plain-English verdict.
Open calculator →Monte Carlo Simulator
Run 1,000 market scenarios on your retirement plan and see your odds of hitting your number.
Open calculator →EPF Calculator
Project your Employees' Provident Fund corpus from your basic salary — India's mandatory retirement savings.
Open calculator →PPF Calculator
See what your Public Provident Fund becomes at 7.1% — tax-free, government-backed, 15-year compounding.
Open calculator →NPS Calculator
Project your National Pension System corpus, tax-free lump sum, and estimated monthly pension.
Open calculator →How to use these tools
Built for curious beginners — no finance degree required.
Plug in your numbers
Type directly or drag the sliders. Every calculator updates instantly — experimenting is the whole point.
Read the chart
Each tool draws your trajectory so you can see compounding, payoff timelines, and trade-offs — not just read a number.
Learn the math
Scroll below any calculator for a plain-English explainer: the formula, a worked example, and the caveats worth knowing.
Why trust the math?
These calculators use the standard time-value-of-money formulas taught in every finance textbook and used by the SEC's own investor tools. We show our work under each calculator, cite our sources, and flag the assumptions — because a number you don't understand is just a guess with better formatting.