Interactive financial education
Use transparent, assumption-driven tools to explore financial concepts that are easier to understand when the math is visible. Each calculator explains its methodology and limitations instead of presenting a result as a forecast or recommendation.
Available now
These calculators are built for general financial education. Change the assumptions, compare scenarios, and use the linked explainers to understand what the outputs mean.
Inflation & real value
Model how a constant hypothetical inflation rate changes the future cost of a basket and the purchasing power of the same nominal dollar amount.
Fund costs & compounding
Compare how two hypothetical annual expense ratios may affect long-term balances when the return and contribution assumptions are held constant.
How to use these tools
Financial calculators are most useful when their assumptions are visible. A small change in an inflation rate, investment return, fee, contribution amount, or time horizon can materially change a modeled result.
Vault of Money tools are designed to make those assumptions explicit and to connect the arithmetic back to the underlying financial concept. They do not predict markets, inflation, interest rates, fund performance, or an individual household's outcome.
Use the calculators to understand relationships and trade-offs, then read the linked educational guides for definitions, context, and limitations.