How we calculate
Transparency is essential for financial tools. This page explains the principles we follow to build and maintain every calculator.
Documented formulas
Every calculator has its formula explained on the page itself, along with the assumptions behind it.
Official, versioned data
Values that change over time are kept in configuration files with a source, update date and validity period. We never make up these numbers.
Estimates, not recommendations
All results are estimates for educational purposes. They are not investment recommendations or personalized accounting/legal advice.
Ongoing review
Every calculator shows the date its methodology was last reviewed. We maintain an internal process to flag outdated data.
No hidden fine print
Limitations and assumptions for each calculation are explained on the calculator page itself.