Your FICO score is a primary driver of your mortgage interest rate. Use our mortgage calculator based on credit score to see exactly how your credit tier affects your monthly payment and total loan cost.
Credit Score Mortgage Calculator
mortgage calculator based on credit score Formula
The core math uses the standard amortization formula, but the critical variable is the Interest Rate (i), which is derived from Loan-Level Price Adjustments (LLPAs) based on your credit tier.
Variables
- M: Monthly Payment.
- P: Principal (Price – Down Payment).
- i: Monthly Interest Rate (Adjusted for Credit Score).
- n: Total Payments (Term * 12).
Related Calculators
- FHA Calculator (Lower Credit Options)
- Debt-to-Income Calculator
- VA Loan Calculator
- Affordability Calculator
How Does Credit Score Affect Mortgage Payments?
When using a mortgage calculator based on credit score, you’ll notice that as your score drops, your rate increases. Lenders view lower scores as higher risk.
For example, the difference between a score of 760+ and 620 can be 1.5% or more in interest rate. On a $300,000 loan, this gap can cost you over $100,000 in extra interest over 30 years.
How to Calculate Mortgage based on Credit Score (Example)
- Identify Tier: Assume your score is 690. This falls into the “680-699” tier.
- Estimate Rate: If the base rate for 760+ is 6.5%, a 690 score might see a rate of 7.0%.
- Compute Payment: A $300k loan at 7.0% results in a payment of ~$1,996/mo.
- Compare: At 6.5% (excellent credit), the payment would be ~$1,896/mo. The lower score costs $100/mo extra.
Frequently Asked Questions (FAQ)
Conventional loans typically require 620+. FHA loans accept scores as low as 580 (with 3.5% down) or 500 (with 10% down).
Yes. A larger down payment reduces the lender’s risk, which can sometimes help you secure a slightly better rate or get approved despite a lower score.
No. This calculator provides estimates based on typical market spreads. Your actual rate will depend on the specific lender, your DTI ratio, and current market conditions.
Paying down credit card debt to lower utilization, fixing errors on your credit report, and avoiding new debt applications can boost your score before applying.