What is my blended rate?
Type the balance and interest rate of each loan. The blended rate calculator weights each rate by its balance to give the one rate that charges the same interest on the total, as lenders do for a first and second mortgage or a student loan consolidation.
- Blended rate
- 3.8%
Your blended rate is 3.8% on $250,000.00.
- Total balance
- $250,000.00
- Interest in a year
- $9,500.00
- Interest in a month
- $791.67
- Rounded up to 1/8%
- 3.875%
- Plain average of the rates
- 5%
Blended rate: 3.8%. Your blended rate is 3.8% on $250,000.00.
The results are estimates for information only. They are not financial, tax, or legal advice. Check the numbers with your lender or a qualified professional before you decide. Terms of use
How to calculate
Works out the blended interest rate of several loans, the average of their rates weighted by balance, with the total yearly interest and the rate rounded up to 1/8% as for a federal consolidation loan.
Example with the default inputs (Loans [Balance $200,000.00, Interest rate 3%; Balance $50,000.00, Interest rate 7%]): Your blended rate is 3.8% on $250,000.00.
Method: blended rate = Σ(balance × rate) ÷ Σ balance; yearly interest = Σ(balance × rate ÷ 100); rounded = ⌈blended × 8⌉ ÷ 8.
- Each balance is weighted by what you owe now; payments and different terms are not modelled.
- Interest in a year and a month is simple interest on today’s balances, before any payment.
- Typed amounts and rates are read exactly, so a shown rate rounds half up from its true value.
- The 1/8% rounding is the federal Direct Consolidation Loan rule; private lenders set their own rates.
Worked examples
Each example is checked against the calculator on every build.
- Loans 200000 3; 50000 7 gives Blended rate 3.8%, Total balance $250,000.00, Interest in a year $9,500.00, Rounded up to 1/8% 3.875%, Plain average of the rates 5%.Source: Rounded up to 1/8%: Federal Student Aid, Student Loan Consolidation (the fixed rate is the weighted average of the interest rates on the loans being consolidated, rounded up to the nearest one-eighth of one percent), https://studentaid.gov/manage-loans/consolidation (retrieved 2026-10-02)
- Loans 5500 5.5; 7500 6.53; 3000 4.99 gives Blended rate 5.887188%, Rounded up to 1/8% 6%, Interest in a year $941.95.Source: Federal Student Aid, Student Loan Consolidation (the fixed rate is the weighted average of the interest rates on the loans being consolidated, rounded up to the nearest one-eighth of one percent), https://studentaid.gov/manage-loans/consolidation (retrieved 2026-10-02)
- Loans 10000 4.5 gives Blended rate 4.5%, Rounded up to 1/8% 4.5%, Interest in a month $37.50.Source: Federal Student Aid, Student Loan Consolidation (the fixed rate is the weighted average of the interest rates on the loans being consolidated, rounded up to the nearest one-eighth of one percent), https://studentaid.gov/manage-loans/consolidation (retrieved 2026-10-02)
How it works
For loans with balances B₁, B₂, … and yearly rates r₁, r₂, … (in percent):
- blended rate = (B₁r₁ + B₂r₂ + …) ÷ (B₁ + B₂ + …)
- total balance = B₁ + B₂ + …
- interest in a year = (B₁r₁ + B₂r₂ + …) ÷ 100, simple interest on today’s balances
- interest in a month = the yearly interest ÷ 12
- rounded up to 1/8% = ⌈blended × 8⌉ ÷ 8, the federal consolidation rule; a rate already on a 1/8 step stays
- plain average = (r₁ + r₂ + …) ÷ the number of loans, counting every row
Each typed amount and rate is read as the exact decimal you typed, so the sums and the division are exact; shown values are rounded once, halves up.
Rules
- 1 to 20 loans. Each balance is from $0 to $10¹², each rate from 0% to 100%. At least one balance must be more than $0.
- A loan with a $0 balance adds nothing to the blend but still counts in the plain average.
Output format. Rates to 3 decimal places, money to the cent.
Worked examples by hand
$200,000 at 3% and $50,000 at 7%. 200,000 × 3 = 600,000 and 50,000 × 7 = 350,000; 950,000 ÷ 250,000 = 3.8%. Interest in a year = 950,000 ÷ 100 = $9,500. Rounded up to 1/8%: 3.8 × 8 = 30.4, up to 31, ÷ 8 = 3.875%. Plain average 5%.
Three student loans. $5,500 at 5.5%, $7,500 at 6.53% and $3,000 at 4.99%: 30,250 + 48,975 + 14,970 = 94,195; 94,195 ÷ 16,000 = 5.8871875%. Interest $941.95 a year. 5.8871875 × 8 = 47.0975, up to 48, so the consolidation rate is 6%.
One loan of $10,000 at 4.5%. The blend is 4.5%, already a multiple of 1/8, so it stays 4.5%. Interest $450 a year, $37.50 a month.
Other questions people ask
What is a blended rate?
A blended rate is the average interest rate of several debts, weighted by how much you owe on each. A big loan at a low rate pulls the blend down more than a small loan at a high rate. It is the single rate that would charge the same interest on your total balance.
How do I calculate a blended interest rate?
Multiply each balance by its rate, add the results, and divide by the total balance. For $200,000 at 3% and $50,000 at 7%: (200,000 × 3 + 50,000 × 7) ÷ 250,000 = 950,000 ÷ 250,000 = 3.8%.
Why not just average the rates?
A plain average treats every loan as the same size. In the example above the plain average of 3% and 7% is 5%, but the interest you pay in a year is $9,500, which is 3.8% of $250,000. The calculator shows both so you can see the difference.
How is a federal consolidation loan rate set?
Federal Student Aid sets a Direct Consolidation Loan’s fixed rate at the weighted average of the rates on the loans you consolidate, rounded up to the nearest one-eighth of one percent. A blend of 5.8871875% becomes 6%.
Does the blended rate tell me if consolidating saves money?
Not by itself. Consolidating at the blended rate charges the same interest in the first year, but a longer term or the rounding up can raise the total you pay. Compare the total interest over each plan’s full term.