Financial guides

Plain-English explanations of the math and reasoning behind each calculator. Guides are being written alongside new calculators — this section will grow over time rather than being filled with mass-produced pages.

Coming soon

How mortgage payments are calculated

The formula behind your monthly payment, step by step.

Coming soon

How compound interest works

Why starting early matters more than starting big.

Coming soon

How to pay off debt faster

Snowball vs. avalanche, explained with real numbers.