Loan Comparison Calculator

Worked example

Example 1: $20,000 at 9.9% for 48 months vs $20,000 at 11.5% for 36 months—lower rate can still cost more interest over a longer term. Example 2: Same rate, 60 vs 36 months—payment drops but interest rises.

When to use this

• Choosing between two lender quotes.
• Comparing term lengths at the same rate.
• Including fees in amount financed.
• Teaching payment vs total interest tradeoffs.
• Personal loan offer bake-offs.

Common examples

• $20k at 9.9%/48 mo vs 11.5%/36 mo—compare total interest.
• Same APR: 60 vs 36 months payment vs cost tradeoff.
• Add origination fee into amount financed on both sides.
• Personal loan vs consolidation offer side by side.
• Pick the lower total cost, not only the lower payment.

Common mistakes

• Comparing only monthly payment.
• Ignoring fees outside APR.
• Mixing secured and unsecured terms casually.
• Assuming approval at advertised rates.
• Treating output as a binding quote.

How it works

Compares two installment loans side by side using standard amortization: monthly payment, total interest, and total cost for each offer so you can choose on total cost—not payment alone.

Limitations

Results are estimates for educational purposes and are not financial or tax advice. Actual costs, rates, and rules vary.

Privacy and file handling

Your data stays on your device and is not uploaded.

Formula or method

PMT = r × L / (1 − (1 + r)^−n) for each loan. Total interest = (payment × n) − principal.