APR explained
APR is the interest rate on your loan expressed annually. It helps compare costs, but it does not tell the whole story by itself.
What APR affects
APR largely determines how much interest accrues each month on your remaining balance. When your balance is high, the same APR creates more interest dollars.
What APR does not show
APR does not directly show fees, term length, or whether a lower payment is coming from extending the loan. A lower APR can still result in higher total cost if the term is extended enough or fees are large.
Practical takeaway
When evaluating a refinance, look at APR, the new term, fees, and break-even timing together. The goal is to understand tradeoffs, not to chase a single number.