Max Rent (30% rule): The most widely cited affordability benchmark. Spending 30% of gross income on rent is considered the upper limit for comfortable housing costs by most financial planners.
Conservative Rent (25% rule): A more cautious threshold that leaves more room for savings, debt payments, and unexpected expenses. Especially useful if you have student loans or are aggressively saving.
Aggressive Rent (35% rule): Acceptable in high-cost cities where 30% may not be realistic, but it leaves less breathing room. Consider this ceiling only if you have low debt and a stable income.
Remaining Income at 30%: What's left of the 30%-rule rent budget after subtracting your existing monthly debts. If this number is low or negative, it signals that your debt load is crowding out housing capacity.
How This Calculator Works
You enter your gross monthly income and any existing monthly debt payments. The tool multiplies income by 25%, 30%, and 35% to produce three affordability tiers. It then subtracts your debts from the 30% figure to show how much rent you can realistically handle once fixed obligations are covered. All calculations use gross (pre-tax) income.
Quick Questions
Should I use gross or net income?
This calculator uses gross (pre-tax) monthly income, which is how the 30% rule is traditionally applied. Some advisors recommend using net income for a more conservative estimate — if so, the 30% result here is already on the aggressive side.
Where did the 30% rule come from?
It originated from the 1981 Brooke Amendment to U.S. public housing law, which capped rent at 30% of income for subsidized housing. It has since become a general rule of thumb for all renters, though it's not a strict financial law.
What counts as "monthly debts"?
Include recurring fixed payments like student loans, car payments, credit card minimums, and personal loans. Don't include variable expenses like groceries or utilities — those come out of your remaining budget.
Is the 30% rule realistic in expensive cities?
In high-cost markets like New York, San Francisco, or Boston, many renters spend 35–50% of income on housing. The 30% rule is a guideline, not a hard limit. The key is ensuring you can still cover essentials, save, and handle emergencies.