Studies
Original data studies built from the Stepwise calculator engine. Every figure is computed from a published formula and reproducible to the cent — free to cite with attribution.
How much interest you really pay on a mortgage
Total mortgage interest across every rate from 3% to 9% and the 15-, 20- and 30-year terms. At 7% over 30 years, every $100,000 borrowed costs $139,511 in interest alone. Every figure reproducible to the cent.
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