// pre-computed reference
25-year mortgage at 8.0%: total interest by loan amount
Exact principal-and-interest figures for a fixed-rate 25-year mortgage at
8.0%, computed with the standard amortization formula. For your own numbers, use the
interactive calculator.
| Loan amount | Monthly P&I | Total interest |
Total paid | Interest % of loan |
|---|
| $100,000 | $772 | $131,543 | $231,543 | 132% |
| $200,000 | $1,544 | $263,091 | $463,091 | 132% |
| $300,000 | $2,315 | $394,634 | $694,634 | 132% |
| $400,000 | $3,087 | $526,183 | $926,183 | 132% |
| $500,000 | $3,859 | $657,725 | $1,157,725 | 132% |
At 8.0% over 25 years, every dollar borrowed costs about
132 cents in interest. A 25-year term trims meaningful interest off the standard 30 without a dramatic payment jump — common in refinances that avoid resetting to a full 30.
See the term comparison or the
extra payment calculator to shrink these numbers.
25-year at other rates: 4.0% · 4.5% · 5.0% · 5.5% · 6.0% · 6.5% · 7.0% · 7.5%
8.0% at other terms: 10-year · 15-year · 20-year · 30-year
Frequently asked questions
How much interest on a $400,000 mortgage at 8.0% for 25 years?
Total interest is about $526,183, with a monthly principal-and-interest payment of $3,087. That's 132% of the amount borrowed, before taxes and insurance.
Is 8.0% a good rate for a 25-year mortgage?
Rates move with the market and your credit profile; compare current quotes from several lenders. Whatever your rate, the table above shows what it costs in total interest.
How can I pay less than $526,183 in interest?
Pay extra toward principal, choose a shorter term, or refinance if rates drop. Use the extra payment calculator to see your exact savings.
How is the 25-year payment at 8.0% calculated?
With the standard amortization formula — P·r(1+r)ⁿ/((1+r)ⁿ−1) — over 300 monthly payments, computed to the cent. The full formula and rounding rules are on our methodology page.