Best Mortgage Calculators for US Home Buyers
Calculate US mortgage payments, affordability, and refinancing options. Tools for all home loan scenarios.
Introduction
The US mortgage market is the largest in the world, offering a unique product unavailable in most countries: the 30-year fixed-rate mortgage. With the conforming loan limit at $806,500 in 2025 and interest rates having normalised from their 2023 peaks, understanding how different loan structures compare is essential for every American homebuyer. These calculators cover every scenario.
Key Calculators
- 30-Year Fixed Mortgage Calculator — The most popular US mortgage. Lower monthly payments but significantly more interest paid over the life of the loan versus a 15-year: Try it →
- 15-Year Fixed Mortgage Calculator — Higher monthly payments but you pay off the home in half the time and pay roughly half the total interest: Try it →
- ARM Calculator — Adjustable-Rate Mortgages (5/1 ARM, 7/1 ARM) start with a lower rate then adjust annually. Model your payment after the initial period: Try it →
- PMI Calculator — Private Mortgage Insurance is required when your down payment is under 20%. PMI typically costs 0.5–1.5% of the loan per year and is cancellable once you reach 80% LTV: Try it →
- Refinance Break-Even Calculator — Divide your closing costs by your monthly savings to find how many months until refinancing pays off: Try it →
Monthly Payment Comparison (Principal + Interest Only)
| Loan Amount | 30yr @ 6.5% | 30yr @ 7.0% | 15yr @ 6.0% |
|---|---|---|---|
| $300,000 | $1,896 | $1,996 | $2,532 |
| $400,000 | $2,528 | $2,661 | $3,375 |
| $500,000 | $3,160 | $3,327 | $4,219 |
Tips for US Homebuyers
A 20% down payment eliminates PMI, which can save $100–$400/month on a typical loan. If you're just under 20%, consider a slightly smaller home that lets you hit that threshold. For ARMs, make sure you understand the caps: a 5/1 ARM might have a 2/2/5 cap structure, meaning the rate can rise 2% at first adjustment, 2% per year after, and 5% total over the life of the loan. The conforming loan limit ($806,500 in 2025) matters because loans above this are jumbo loans with stricter qualifying requirements.