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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Editorial standards

How I Write and Review This Site

I write and review the calculator explanations, worked examples, and educational articles. Formulas and assumptions are documented so readers can reproduce the examples and understand what each result leaves out.

Transparent assumptions

Return, inflation, contribution timing, dividend treatment, and known exclusions are labelled instead of hidden behind one result.

Reproducible examples

Worked examples show the inputs and formulas needed to check the arithmetic independently.

Clear limits

Content is educational, not personalized financial advice, and is updated when the calculator or its documented assumptions change.

Review the full calculation methodology or use the contact page to report a correction.