Small Business Loan Calculator

How to Use This Calculator

Enter three numbers: how much you want to borrow, the annual interest rate your lender quoted, and the repayment term in months. Hit Calculate and the tool does the rest using the standard amortization formula lenders themselves use.

Here is what each result means:

• Monthly Payment — the fixed amount you pay every month for the full loan term. This never changes on a fixed-rate loan.
• Total Interest Paid — the total dollars paid to the lender above and beyond the principal you borrowed. This is the true cost of the loan.
• Total Amount Paid — principal plus total interest, i.e., the grand total that leaves your bank account over the life of the loan.
• Total Cost of Borrowing — total interest paid expressed as a percentage of the original loan amount over the full loan term. Useful for understanding the true cost of the loan.

Concrete example: borrow $50,000 at 7.5% annually over 36 months. The monthly payment is $1,554.18. You pay $5,950.39 in total interest, for a grand total of $55,950.39. That is 3.97% effective annual cost — a reasonable deal for a well-qualified borrower with an SBA or bank loan.

What Lenders Actually Look At

Running the numbers in a calculator is step one. Before you walk into a lender's office, understand the five factors that decide whether you get approved — and at what rate.

1. Personal credit score. Most SBA lenders require a minimum personal FICO of 680. Traditional banks often want 700+. Online lenders like OnDeck accept scores as low as 600, but you will pay for it — rates on those products often run 25–99% APR. If your score is below 680, spending 6–12 months improving it before applying can save you tens of thousands of dollars in interest.
2. Time in business. Most banks and SBA lenders want to see at least 2 years of operating history. Lenders use this as a proxy for stability. Businesses under 2 years often need to turn to SBA Microloans, CDFI lenders, or online platforms that specialize in early-stage businesses.
3. Annual revenue. Lenders check whether your revenue can support new debt payments. A common rule: your annual loan payments should not exceed 10–15% of gross annual revenue for a comfortable approval. If your business earns $200,000 a year, lenders are generally comfortable with up to $20,000–$30,000 in annual debt service from a new loan.
4. Debt service coverage ratio (DSCR). This is the single most important underwriting metric for SBA loans. DSCR = net operating income ÷ total annual debt payments. The SBA standard minimum is 1.25. A $100,000 net operating income business can support up to $80,000 in annual debt payments and still clear the 1.25 threshold. Lenders calculate this before you even see a term sheet.
5. Collateral. SBA 7(a) loans above $25,000 generally require collateral — business assets first, then personal real estate if business assets are insufficient. Banks typically want collateral to cover 80–100% of the loan amount. Online lenders often require only a general lien on business assets (UCC-1 filing) rather than specific collateral.

SBA vs. Term Loans vs. Lines of Credit

Not all small business debt is the same. The table below summarizes the four most common loan products so you can use this calculator with realistic inputs for each one.

Note: SBA 7(a) variable rates are tied to the WSJ Prime Rate plus a lender spread. Rates shown reflect 2025 market conditions. Online lender rates often use factor rates (1.1–1.5) rather than APR — always convert to APR before comparing.

Frequently Asked Questions

Disclaimer: This calculator is for informational purposes only and does not constitute financial advice. Loan terms, rates, and eligibility vary by lender and change over time. The results shown assume a fixed rate and equal monthly payments with no fees. Always consult a licensed financial advisor or loan officer before making borrowing decisions.

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