Business loan calculator: monthly payment, interest and APR (2026)
Edited by Moe Ameen · Published
A business loan calculator turns the loan amount, interest rate and term into a monthly payment with the standard amortization formula. Borrow $100,000 at 10% over 10 years and you'd pay about $1,321.51 a month and $58,581 in total interest. An origination fee pushes the APR above the interest rate. On variable-rate SBA 7(a) loans, the SBA caps the rate at the base rate plus 3 to 6.5 percentage points, depending on loan size.
Key takeaways
- Monthly payment = loan × r(1+r)^n ÷ ((1+r)^n − 1), where r is the monthly rate and n the number of payments.
- A longer term lowers the payment and raises the total interest.
- An origination fee raises the APR, and by more on a short loan.
- SBA 7(a) variable rates top out at the base rate plus 3 to 6.5 points, depending on loan size.
- Most 7(a) loans run 10 years or less. Real estate can stretch to 25.
How is a business loan payment calculated?
Multiply the loan amount by r(1+r)^n and divide by (1+r)^n minus 1. Here r is the monthly rate and n is the number of payments.
That's the standard amortization formula Investopedia gives [1]. The monthly rate is the annual rate divided by 12. For $100,000 at 10% over 120 months, r is about 0.00833, and the payment works out to $1,321.51. Each payment covers that month's interest first, and the rest goes to principal, so the share going to principal grows over time [1].
How much interest will you pay over the life of the loan?
Multiply the payment by the number of payments, then subtract what you borrowed. A longer term means a lower payment but more interest.
| Term | Monthly payment | Total interest |
|---|---|---|
| 3 years | $3,226.72 | $16,161.87 |
| 5 years | $2,124.70 | $27,482.27 |
| 10 years | $1,321.51 | $58,580.88 |
| 25 years | $908.70 | $172,610.22 |
How does an origination fee change the APR?
APR counts fees as well as interest, so any fee pushes it above the interest rate. The shorter the loan, the bigger that jump gets.
The CFPB says the interest rate doesn't reflect fees, while the APR includes the rate plus points, broker fees and other charges [2]. NerdWallet puts business loan origination fees at 1% to 5% of the loan in most cases, and as high as 10% [3]. It estimates 0.5% to 1% at conventional banks and 1% to 10% at online lenders [3].
NerdWallet's examples show the effect of term [3]. On $100,000 at 8% with a 5% fee, the APR is 17.28% over 12 months but 10.09% over 60 months. Depending on the loan, a fee may be added to the balance or taken out of the money you receive. The calculator handles both.
What's the maximum interest rate on an SBA 7(a) loan?
On a variable-rate 7(a) loan, it's the base rate plus 6.5 points at $50,000 or less, falling to plus 3 points above $350,000.
| Loan amount | Maximum rate |
|---|---|
| $50,000 or less | Base rate + 6.5 points |
| $50,001 to $250,000 | Base rate + 6.0 points |
| $250,001 to $350,000 | Base rate + 4.5 points |
| Over $350,000 | Base rate + 3.0 points |
The base rate is either the prime rate in effect on the first business day of the month or the SBA's Optional Peg Rate, which it publishes quarterly [5]. You and the lender negotiate the actual rate, under those ceilings [4]. Fixed-rate ceilings are published separately by the SBA [4][6]. The 7(a) loan maximum is $5 million [7].
How long can an SBA 7(a) loan last?
Usually 10 years or less. Loans for real estate, or for equipment that lasts longer than 10 years, can run up to 25 years with extensions.
The SBA says the term should be the shortest that fits the borrower's ability to repay [4]. Loans of 15 years or longer carry a prepayment fee in the first three years: 5% of the amount prepaid in year one, 3% in year two and 1% in year three [4]. The SBA doesn't allow balloon payments on 7(a) loans [5]. For the rest of the program, see SBA loans explained.
Glisten tool
Business loan calculator
Glisten tool · Business loan calculator
— a month
Enter a loan amount, a rate from 0 to 100% and a term of 1 to 600 months. Leave the fee blank if there isn't one.
SBA 7(a) rate ceiling (variable rate)
Enter a loan amount and today's base rate to see the most an SBA lender can charge on a variable-rate 7(a) loan.
Estimates only. Your lender's quote and loan agreement set the real numbers. This runs in your browser, and nothing you type is sent anywhere or saved.
We checked the APR math against NerdWallet's three worked examples [3]. With the fee added to the loan, it matches all three: 11.89%, 17.28% and 10.09%. With the fee taken out of the money you receive, the APR comes out a little higher, because you pay interest on money you never got.
Is this right for you?
Best for
- Comparing loan offers by monthly payment, total interest and APR.
- Seeing the highest variable rate an SBA lender can charge on your loan size.
Not ideal for
- Lines of credit, where the balance and payment change as you draw and repay.
- Variable-rate loans after the rate moves. The calculator holds one rate for the whole term.
Frequently asked questions
How do I calculate a monthly business loan payment?
Multiply the loan amount by r(1+r)^n and divide by (1+r)^n − 1, where r is the annual rate ÷ 12 and n is the number of months [1].
What's the difference between the interest rate and the APR?
The rate is the yearly cost of borrowing without fees. The APR adds fees and other charges [2].
How much is a business loan origination fee?
NerdWallet says 1% to 5% of the loan in most cases, and up to 10% [3].
What is the maximum interest rate on an SBA 7(a) loan?
For variable rates, the base rate plus 6.5 points on loans of $50,000 or less, down to plus 3 points above $350,000 [4][5].
Can I pay off an SBA 7(a) loan early?
Yes. Loans of 15 years or longer carry a fee in the first three years: 5%, then 3%, then 1% of the amount prepaid [4].
Is the calculator private?
Yes. It runs in your browser, and nothing you type is sent anywhere or saved.
How we know this
On October 29, 2026 we read Investopedia's amortization page, the CFPB's page on interest rate vs APR, NerdWallet's guide to business loan origination fees, the SBA's 7(a) borrower page and its 7(a) terms page for lenders, and 13 CFR 120.213 and 120.214 in the eCFR. Example figures are our own arithmetic. The calculator's APR solves for the rate at which your payments equal the cash you receive.
- Amortization schedule: definition, formula, and calculation, Investopedia. Checked October 29, 2026.
- What is the difference between a mortgage interest rate and an APR?, Consumer Financial Protection Bureau. Checked October 29, 2026.
- Business loan origination fee: definition and cost, NerdWallet. Checked October 29, 2026.
- 7(a) terms, conditions and eligibility, SBA. Checked October 29, 2026.
- 13 CFR 120.214: What conditions apply for variable interest rates?, eCFR. Checked October 29, 2026.
- 13 CFR 120.213: What fixed interest rates may a Lender charge?, eCFR. Checked October 29, 2026.
- 7(a) loans, SBA. Checked October 29, 2026.