Weighted Average Interest Rate Calculator for Multiple Loans
Calculate the weighted average interest rate across all your loans instantly. Enter balances and APRs — get your blended rate in seconds. Free and accurate.
Loan Details
Weighted Average
Frequently Asked Questions
Stop guessing what debt costs you. Our weighted average interest rate calculator reveals your true blended APR — so you can pay smarter and hit FIRE faster.
A: A weighted average interest rate is a single blended rate that reflects the true cost of your entire debt portfolio. Unlike a simple average, it accounts for each loan's balance relative to your total debt. A larger loan carries more weight — so it pulls the blended rate closer to its own APR. This gives you a far more accurate picture of what you're actually paying.
A: Multiply each loan balance by its APR, sum all those products, then divide by your total loan balance. Formula:
Weighted Average APR = Σ (Loan Balance × APR) ÷ Total Balance
Example: A $5,000 loan at 3% and a $15,000 loan at 7% gives a weighted average of 6.0% — not 5.0% as a simple average would suggest.
A: It shifts immediately. Pay off your highest-balance loan and the remaining loans recalculate as a share of a smaller total. If that paid-off loan also carried the highest APR, your blended rate drops significantly. Use the calculator to model this — enter a $0 balance for any loan and watch the weighted average update in real time.
A: A simple average treats every loan equally regardless of size. A weighted average scales each rate by how much you actually owe. For debt decisions, the simple average is misleading. If you have a $500 loan at 20% and a $50,000 loan at 4%, your simple average is 12% — but your weighted average is just 4.07%. Always use the weighted figure when evaluating refinancing or consolidation.
A: A consolidation loan makes financial sense only if its fixed rate is lower than your current weighted average APR. Most financial planners flag anything above 7–8% as a consolidation candidate. If your blended rate sits below 4%, consolidation rarely saves money after fees. Run this calculator first — it gives you the benchmark number to bring to any lender conversation.
A: Yes. Enter all your federal and private student loans with their respective balances and APRs. The resulting weighted average is the minimum rate a refinanced loan must beat to save you money. Keep in mind: refinancing federal loans into private ones forfeits income-driven repayment and forgiveness options — factor that into your decision beyond the rate alone.
A: Every percentage point in blended rate directly extends the time you carry debt — and delays wealth-building. A portfolio weighted at 6% vs. 3% can cost tens of thousands in extra interest over a decade. Paying down higher-APR loans first (the avalanche method) lowers your weighted average faster, freeing up cash flow to invest. Use this calculator monthly to track that rate dropping as you execute your payoff strategy.
A: No. Monthly payment is optional and does not influence the weighted average APR — that figure depends solely on balances and interest rates. The payment field is included for your reference, so you can track your total monthly debt obligation alongside your blended rate in one place. Both numbers matter when stress-testing your monthly budget.