Compound Interest
See how a starting amount and monthly contributions grow over time, and how much of the result is interest.
Open calculator →Loan Calculator
Work out the monthly payment, total interest and true cost of a loan or mortgage over its full term.
Open calculator →Debt Payoff
Compare the snowball and avalanche methods across all your debts and see which clears them fastest.
Open calculator →These answer one question at a time.
Manticore Finance answers them all at once, on your real numbers — projections, loan tracking, fee drag and debt payoff woven into one live picture of your net worth. One desktop app, entirely offline.
Why these are private by default
Every calculator here runs as plain JavaScript in your own browser. There is no server doing the maths, no form being submitted, and no analytics watching what you type — your figures never leave your device. That's not a marketing line bolted onto a tool; it's the same design principle the desktop app is built on, where your entire portfolio lives on your machine and nothing phones home.
Get notified when new tools drop
We're adding more free calculators and shipping updates to the Manticore Finance app. Leave your email and we'll tell you when something new lands — no spam, unsubscribe anytime.