Financial clarity,
without the sales pitch.
Compoundulator is a suite of free financial calculators and planning tools built on one belief: the math behind your biggest money decisions should be transparent, fast, and free — not buried behind a lead-capture form or a advisor's commission.
Why we built this
Most online financial calculators are either too simplistic to trust or so cluttered with ads and upsells that the answer gets lost. The good ones are often gated behind an email signup or a bank's product funnel, where the "recommendation" conveniently points at whatever they sell.
We wanted tools we'd actually use ourselves: rigorous enough to model real decisions — paying off debt, refinancing, renting versus buying, planning for retirement — and honest enough to tell you when the answer is "it depends." Everything is backed by published formulas and runs in real time as you type.
What we stand for
Open math, no black boxes
Every result traces back to a formula we publish on our methodology page. If you want to check our work, you can — down to the equation.
Free to use
All eight calculators are free, with no signup required to run the numbers. An optional account lets you save your data across tools.
Privacy-first
Run any calculator without an account and your inputs stay in your browser. If you create an account, your data is yours — we never sell it.
Decision-grade clarity
Numbers are only useful if they change a decision. Each tool ends with a clear takeaway, not just a wall of figures.
How the math works
We don't ask you to take our word for it. Every calculator's formulas and assumptions are documented on our methodology page — from mortgage amortization to the 4% retirement rule.
A note on advice
Compoundulator is an educational tool, not a licensed financial, tax, or investment advisor. Our calculators and AI advisor are designed to inform your thinking and help you ask better questions — not to replace personalized advice from a professional who knows your full situation.
Get in touch
Questions, corrections, or a formula you'd like us to add? Email hello@compoundulator.com. We read everything.