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What Interest Rate Gives the Total Interest I Want to Pay

On a $300,000 loan over 30 years, paying exactly $200,000 in total interest implies a rate of about 5.19%. That is well below typical recent market rates, so reaching it would require a strong credit profile, points, or a shorter term. Compared with a 7% loan (which costs about $418,000 in interest), hitting 5.19% would save roughly $218,000. The calculator finds the rate by solving the amortization formula backwards for the rate.

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RateFig provides estimates for educational purposes only. Mortgage and loan figures depend on your credit, fees, points, and individual lender terms. This is not financial advice. Confirm every number with a qualified loan officer before making a decision.

How It Works

Total interest equals all payments minus principal: n×P − L, where the payment P itself depends on the rate. Setting n×P(r) − L = target and solving for r has no closed form, so we use bisection: we test monthly rates between 0% and 60%, compute the payment at each, and narrow in until the implied total interest matches your target. The required annual rate is that monthly rate times 12. The curve charts total interest across nearby rates so you can see how sensitive the cost is.

What Should You Do?

If the required rate is far below what lenders quote, you have three realistic levers: improve your credit score, pay discount points to buy the rate down, or shorten the term. A shorter term raises the payment but can drop the rate and slashes total interest. Get written rate quotes from at least three lenders and compare the APR, not just the advertised note rate, because fees change the real cost.

Frequently Asked Questions

Why is my required rate so low?

A small total-interest target means you want to pay back close to principal only, which needs a very low rate. Market rates may simply not reach it without points or a short term.

What are discount points?

Points are upfront fees (about 1% of the loan per point) that lower your rate. They pay off only if you keep the loan long enough for the saved interest to exceed the fee.

Does this account for fees?

No, it solves on the note rate and principal only. Fees raise your effective APR, which you can compare with our multi-lender tool.

How does credit score affect my rate?

Higher scores typically earn lower rates. Even a 0.5% rate drop can save tens of thousands over 30 years.

Is a shorter term always better?

It saves interest but raises the monthly payment. Choose the shortest term whose payment you can comfortably afford.

Should I trust this rate to shop?

Use it as a target when negotiating, but final rates come from a formal lock with a specific lender.