One Calculator Suite for Borrowing Costs
This suite combines the fixed-payment formula, mortgage down-payment math, amortization schedules, and payoff acceleration scenarios in one place. The core monthly payment formula is still M = P x [r(1+r)^n] / [(1+r)^n - 1], where P is principal, r is the monthly interest rate, and n is the number of payments.
The value of seeing these modes together is context. A generic loan payment, a mortgage payment, an amortization table, and an extra-payment payoff plan are not four unrelated questions. They are different views of the same borrowing decision: how much you pay each month, how interest changes over time, and what happens if you reduce principal faster.
All calculations run in your browser. The results are estimates for education and planning, not lender quotes or financial advice. Real loans may include taxes, insurance, PMI, origination fees, variable rates, prepayment penalties, or escrow requirements that are not part of the basic formula.
How to Use the Suite
- 1Choose the tab that matches your question: loan payment, mortgage payment, amortization schedule, or payoff strategy.
- 2Enter the loan amount, rate, term, and any mortgage-specific fields such as down payment.
- 3Review the monthly payment, total interest, schedule, or payoff comparison generated in the browser.
- 4Switch tabs to compare the same borrowing scenario from another angle before making decisions.
When You'll Use This
Comparing car loan offers from different dealers
Dealer A offers $30K at 5.9% for 60 months, Dealer B offers $30K at 4.9% for 72 months. Which costs less total? Plug both in. The lower rate with longer term might actually cost more in total interest ($4,700 vs $4,600 in this case). Monthly payment isn't everything.
Deciding between a shorter or longer loan term
A 3-year personal loan at 8% means $940/month on $30K but only $3,860 total interest. A 5-year term drops to $608/month but costs $6,497 in interest. Is the $332/month savings worth $2,637 more in interest? This calculator makes the tradeoff visible.
Figuring out how much you can afford to borrow
You can afford $500/month. At 7% for 5 years, that means you can borrow about $25,000. At 7% for 3 years, only about $16,500. Work backwards from your budget to find your borrowing limit.
Calculating the impact of a rate difference
Your credit score qualifies you for 6% vs 8%. On a $20K loan for 4 years, that's the difference between $2,540 and $3,420 in total interest. That's $880 saved just from a better rate. Worth improving your credit score before applying.
Things to Know
APR vs interest rate: they're not the same
The interest rate is just the cost of borrowing. APR (Annual Percentage Rate) includes fees, origination charges, and other costs rolled into an equivalent rate. A loan at 5% interest with $1,000 in fees might have a 5.8% APR. Always compare APR to APR, not rate to APR.
Longer terms = lower payments but way more interest
A $25K loan at 6%: 3-year term = $760/month, $2,370 interest. 5-year term = $483/month, $3,999 interest. 7-year term = $365/month, $5,659 interest. You pay $3,289 more for the "convenience" of lower monthly payments. Always pick the shortest term you can afford.
Extra payments save more than you think
Adding $100/month to a $30K, 5-year, 6.5% loan saves $850 in interest and pays it off 9 months early. The earlier you make extra payments, the more you save, because you're reducing the principal that interest is calculated on.
This calculator shows principal + interest only
Real loan costs may include origination fees (1-5% of loan), late payment fees, prepayment penalties, and for auto loans: gap insurance. For mortgages: property tax, homeowner's insurance, PMI. Factor these in separately.
Examples
$25,000 auto loan at 6.5% for 5 years
A typical new car loan scenario.
Input
Principal: $25,000 | Rate: 6.5% | Term: 5 yearsOutput
Monthly: $489 | Total Interest: $4,352 | Total Cost: $29,352$10,000 personal loan at 9% for 3 years
A common personal loan for debt consolidation.
Input
Principal: $10,000 | Rate: 9% | Term: 3 yearsOutput
Monthly: $318 | Total Interest: $1,448 | Total Cost: $11,448Limitations
- Assumes fixed interest rate for the entire loan term. Does not model variable-rate or adjustable-rate loans.
- Does not include fees (origination, closing costs, PMI, insurance) in the calculation. Actual monthly obligations may be higher.
- Results are estimates for planning purposes. Your actual loan terms will depend on your lender, credit score, and application.
- Compound interest is calculated monthly only. Does not support daily or continuous compounding.
Features
- Standard amortization formula, the same math banks use
- Shows monthly payment, total interest, and total cost
- Works for any fixed-rate loan (auto, personal, student)
- Instant results as you type. No submit button needed
- No signup, no personal information collected
- Runs 100% in your browser. Your financial data stays private
Frequently Asked Questions
Why combine the loan, mortgage, amortization, and payoff calculators?
They all answer the same borrowing-cost workflow. Combining them reduces duplicate pages and lets you compare monthly payment, interest, schedule, and payoff effects from one place.
Is this different from the old loan calculator?
Yes. The old calculator only estimated a fixed loan payment. This suite adds mortgage-specific inputs, amortization schedules, and payoff comparisons while keeping the same private browser-based calculation model.
Can I use this for a mortgage decision?
Use it to understand the math and compare scenarios. It does not include every real-world mortgage cost, such as taxes, insurance, PMI, closing costs, escrow, variable rates, or lender-specific fees.
Are the calculations uploaded to a server?
No. Inputs and results stay in your browser. The page uses client-side JavaScript for calculations and does not upload your loan amounts or rates.
Can I rely on the result as financial advice?
No. The tool is for education and planning. Confirm actual loan terms with a lender or qualified financial professional before making commitments.
Last reviewed:
Your Privacy
All calculations happen entirely in your browser. No financial data is uploaded to any server. Your loan amounts, income, and interest rates never leave your device.
Detailed guide
How to Read Amortization Schedule: A Clear Guide
A plain-English guide to reading amortization schedules: what each column means, why the interest-to-principal ratio shifts over time, and how to use it to save money.
Read guideRelated Financial Workflows
- For a quick one-period interest estimate, use the Interest Calculator.
- To plan monthly cash flow around a new payment, try the Budget Planner.
- For savings growth rather than debt payoff, compare with the Compound Interest Calculator.