All Calculators
Every Caspenda calculator runs instantly in your browser, shows its exact math, and is shareable with a link. No sign-up, no tracking.
Growth & Compounding
How contributions and returns compound together — from one-off sums to steady investing.
Compound Interest
See how your balance grows year by year, and how much of it is growth, not your own money.
Open calculator →Dollar-Cost Averaging
Model steady monthly, biweekly or weekly investing and watch your contributions compound.
Open calculator →DCA vs Lump Sum
Same budget, same time, side by side. See exactly how much one strategy can beat the other.
Open calculator →Rule of 72
How long until your money doubles? The fastest mental shortcut in finance.
Open calculator →Investment Return
Work backwards from your final balance to your real annualized return.
Open calculator →Retirement & FIRE
Turn your retirement goal into a number — a target balance, a timeline, or a safe withdrawal rate.
Retirement
Project your nest egg and how much you can safely withdraw each month.
Open calculator →FIRE Calculator
Find your FIRE number and how many years to financial independence.
Open calculator →Coast FIRE
The lump sum you need today so compounding can finish the job.
Open calculator →4% Rule
Find the portfolio you need to support your retirement spending.
Open calculator →Savings Goal
Work backwards from a target amount to the monthly contribution you need.
Open calculator →Portfolio & Fees
See what fees and market returns really do to a long-term portfolio — and what you own, net.
Portfolio Growth
See contributions, growth and fees separately — and what fees cost you over decades.
Open calculator →ETF Fee Impact
Compare two ETFs and see what a small expense ratio gap costs you over decades.
Open calculator →Net Worth
Everything you own minus what you owe — your true financial position.
Open calculator →Inflation & Debt
Measure the quiet costs: how inflation erodes cash and how loan payments add up.