Fortune Orb

Free, and no account needed

What do you want to figure out?

Pick a question. Each calculator answers it in plain words, then shows the year-by-year math behind it.

See all 6 calculators

Try it: investment growth

In 10 years you would have

$125,869

$10,000 to start and $500 a month at 10% a year. You put in $70,000 and earn $55,869.

Open the full breakdown

Built to be trusted

Shows its work

Every result comes with the year-by-year table it came from.

Stays on your device

The math runs in your browser. Nothing you type leaves your device unless you sign in and save it.

Shareable by link

Your inputs live in the URL, so a link opens the same scenario for anyone.

How it works

Three steps, no sign-up

  1. Pick a question

    Start from what you want to know, not from a formula name.

  2. Adjust a few numbers

    Sensible defaults are filled in. The answer updates as you type.

  3. Keep or share it

    Copy the link, or sign in to save it under a name.

How the numbers are made

Optional account

Sign in when you want to keep something

No bank connection required.
  • Saved scenarios that follow you to any device.
  • A net worth dashboard built from a profile you fill in once.
  • A retirement plan that shows which years are funded.