Mortgage Rate Compare Tool
Compare up to three mortgage rate offers side by side. See monthly payments and total interest so you can choose the rate that best fits your budget and long-term plans.
Mortgage rate comparison formulas
Comparing mortgage rates is fundamentally about understanding how the interest rate affects your monthly payment and total interest over the life of the loan. This calculator uses standard fixed-rate formulas to compute those values for each rate option.
1. Monthly interest rate
Monthly rate (r) = Annual rate (%) ÷ 100 ÷ 12
This converts the annual percentage rate into a monthly decimal rate used in the payment formula.
2. Fixed-rate mortgage payment
n = Years × 12
Payment = L × r ÷ (1 − (1 + r)^(-n))
Where:
L = loan amount
r = monthly interest rate
n = total number of monthly payments
This formula produces a level monthly payment that fully amortizes the loan over the chosen term.
3. Total interest over the term
Total paid = Payment × n
Total interest = Total paid − L
Once the payment is known, multiplying by the number of months gives the total amount paid. Subtracting the original loan amount yields total interest.
By applying these formulas to each rate option, the calculator shows how small changes in rate can produce large differences in total interest, even when monthly payments look similar.
How to compare mortgage rate offers effectively
When you shop for a mortgage, you’ll often receive multiple rate quotes from different lenders or for different scenarios (for example, with or without points). At first glance, the differences may seem small—5.99% vs. 6.25%—but over 15 or 30 years, those differences can add up to thousands of dollars in interest.
This tool helps you compare rate offers in a structured way. You enter a single loan amount and term, then add up to three rate options with their associated point or fee costs. The calculator computes the monthly payment and total interest for each option, then highlights which one has the lowest payment and which has the lowest total interest.
Payment vs. total interest
It’s common to focus on the monthly payment because it directly affects your budget. A lower payment can make it easier to qualify or feel comfortable with the loan. However, the lowest payment is not always the best long-term choice. A slightly higher payment with a lower rate may reduce total interest significantly.
The comparison table shows both metrics side by side. You might see that one option has the lowest payment but higher total interest, while another has a slightly higher payment but much lower total interest. This lets you decide whether you prefer immediate cash flow or long-term savings.
Worked example
Suppose you’re borrowing $350,000 for 30 years. You receive three offers:
- Option 1: 6.25% with no points.
- Option 2: 5.99% with $2,500 in points.
- Option 3: 5.75% with $5,000 in points.
Using the calculator, you’ll see the monthly payment for each rate and the total interest over 30 years. Option 3 may have the lowest payment and lowest total interest, but it also requires the highest upfront cost. If you plan to stay in the home for a long time, paying points to secure a lower rate can make sense. If you expect to move or refinance again in a few years, the upfront cost may not be worth it.
Incorporating extra principal
The extra monthly principal input lets you model a scenario where you pay a bit more each month than required. While the comparison table focuses on the base payment, the summary highlights the lowest payment and interest assuming the extra principal is applied consistently. This can show how aggressive repayment strategies interact with different rates.
Practical tips
- Use labels to track which lender or scenario each rate represents (for example, “No points”, “1 point”, “Credit union”).
- Compare offers with the same term to isolate the impact of the rate; then, if needed, run separate scenarios for different terms.
- Ask lenders for a loan estimate that clearly shows points, fees, and APR, then use those numbers in the tool.
- Consider how long you plan to stay in the home—paying points for a lower rate usually makes more sense if you’ll keep the loan for many years.
Ultimately, the “best” rate is the one that aligns with your budget, risk tolerance, and time horizon. This calculator gives you a clear, quantitative view of the trade-offs so you can make a confident decision.
Frequently Asked Questions
Can I compare more than three rates?
This version supports up to three rate options at once. If you have more offers, run multiple comparisons or focus on the most competitive quotes.
What should I enter for points or fees?
Enter the total upfront cost associated with each rate option, including points and lender fees that differ between offers. This helps you weigh lower rates against higher upfront costs.
Does the tool use APR?
The tool uses the nominal interest rate you enter, not APR. APR incorporates certain fees into an effective rate. You can use APR for comparison, but most lenders quote and price loans based on the nominal rate.
Can I model different terms?
All options share the same term in this tool. To compare a 15-year vs. 30-year mortgage, run separate scenarios and compare the results.
Is this financial advice?
No. This tool is for education and planning. It helps you visualize payment and interest differences, but it is not personalized financial advice. Consider speaking with a qualified advisor or lender before making decisions.
Can I export the comparison?
Yes. Use the Export CSV button to download the comparison table. You can import it into a spreadsheet or share it with a lender or advisor.
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Information on this site is for educational purposes only and is not financial, tax, or legal advice. Calculations are estimates and may not reflect actual results. See our Privacy Policy and Disclaimer.