The front-loaded truth
On a $357k loan at 6.5%, the first payment sends about $1,933 to interest and $323 to principal. The ratio takes roughly 15 years to reach 50/50. This is not a bank trick — it is how amortization prices time — but it explains why extra payments early are so disproportionately valuable and why "just wait, principal paydown accelerates" is technically true and financially painful.
Interest vs price: the real bill
That loan repays $357k of principal and roughly $455k of interest — the house costs 2.3× its price across the term, before taxes and upkeep. Run the payment calculator and look at the total-interest line before negotiating: a 0.25% rate improvement is often worth more than a $10k price cut, and it is frequently the easier negotiation.
Using the schedule instead of fearing it
Every extra principal dollar stops future interest permanently. The extra-payment calculator turns that abstract fact into a date: months saved, dollars saved, new payoff year. Borrowers who internalize this one page stop seeing the mortgage as weather and start seeing it as a lever.