Mortgage Calculator: How Much House Can You Actually Afford?

Most mortgage calculators give you a monthly payment and call it a day. That number is almost useless without context.

What you actually need to know before you buy:

• Total interest paid over the life of the loan — on a $350,000 30-year mortgage at 6.5%, you'll pay $446,000 in interest. That house costs $796,000.
• How a shorter term changes the picture — a 15-year mortgage at the same rate: monthly payment goes up $600, total interest drops by $240,000.
• What one extra payment per year does — on that same 30-year loan, one extra payment annually pays it off 4-5 years early and saves $60,000-80,000 in interest.

The Number Banks Don't Lead With

Your bank pre-approves you for the maximum you can borrow. That's not a recommendation — it's a limit. The question isn't what you qualify for; it's what payment leaves you with enough cash flow to actually live your life.

The general rule: housing costs (PITI — principal, interest, taxes, insurance) should be 28% or less of gross monthly income. If you're at 35-40%, you're house-poor on paper even if the bank says yes.

Points: Pay More Now or More Later?

Discount points let you buy down your interest rate — each point costs 1% of the loan and typically reduces your rate by 0.25%. Whether that makes sense depends entirely on your break-even timeline.

If you're paying $3,500 to save $45/month, you break even in 78 months. If you're confident you'll be in the house for 10+ years, that's smart math. If you might move in 4 years, you're paying to save someone else money.

Our mortgage calculator handles all of this — payment, amortization schedule, extra payment scenarios, and points break-even — in one place.

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This article is for informational purposes only. See our disclaimer.