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Hello, I'm Katrina

I Build Practical Tools That Are Easy to Use

Everything is designed to make scenarios easy to understand, compare, and sanity-check.

The S&P 500 Calculator started as a tool I built for myself. When I tried to model my own investing, most calculators were either hard to use or missing the outputs I actually needed.

So I built the version I wanted to use:

  • 4 calculation modes to solve different questions, not just one final number
  • Clear visual comparisons, so you can see how contributions, gains, and inflation affect results over time
  • Charts and icons that guide your eye, instead of dense tables you have to decode
  • Year-by-year breakdown, showing exactly how your balance evolves
  • Transparent assumptions, with every input visible and adjustable

I hope it helps you plan and compare scenarios more clearly.

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