How Rent Affordability Is Measured

On $60,000/year ($5,000/month gross), the 30% rule suggests $1,500 rent; landlords using the 40× rule would accept up to $1,500 too ($60,000 ÷ 40). After $300 of debts, you'd have $3,200 left each month for everything else.

Three Rules, One Answer

The 30% rule protects your own budget, the 40× rule is what landlords actually check, and the 36% debt-to-income cap is what lenders apply. A rent number that clears all three — as $1,500 does here — is safe from every angle. If they disagree, the strictest one wins: the landlord's requirement you cannot negotiate away is the real ceiling.

Beyond the Rules

Rules assume a standard budget. Adjust them for reality: expensive cities, student loans in income-driven repayment, side income, or a partner contributing to rent. The rules give a starting ceiling; your actual comfort zone depends on your spending, savings rate, and how much buffer you want each month.