Rent Affordability Calculator (3x Rule) - Rental Flow
Landlord Calculator

Rent Affordability Calculator

A quick screening tool for applications: the "3x rule" of thumb estimates the gross annual income a tenant typically needs to comfortably afford a given monthly rent.

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What this calculator does

Many landlords and screening services use a multiple of monthly rent, commonly 3x, as a quick income benchmark when reviewing applicants. This calculator flips the rent into the required annual income, and lets you adjust the multiplier if your market or policy uses a different rule.

The formula

Required Annual Income = Monthly Rent × 12 × Income Multiplier

This is a screening heuristic, not a legal requirement. Check your local fair housing rules before applying any income standard as a hard cutoff.

Worked example

$1,500/month rent, 3x multiplier

Monthly rent$1,500
Income multiplier3x
Required annual income$54,000

$54,000 a year would be the typical income benchmark for this rent under a standard 3x rule.

How much income should a tenant have?

A widely used guideline is that a tenant's gross monthly income should be about three times the rent, sometimes called the 3x rule. For $1,500 rent, that points to roughly $4,500 in monthly income. It is a screening guideline, not a law, and many landlords adjust the multiple for their market.

Income is only one factor. Pair the affordability check with credit history, rental references, and stable employment to get a full picture. The multiple helps you set a consistent, fair baseline so every applicant is measured the same way.

Try it with your own numbers →

Frequently asked questions

The 3x rule suggests a tenant's gross monthly income should be at least three times the monthly rent, so the rent is about a third of their income. It is a common affordability screen that helps landlords gauge whether an applicant can comfortably cover the rent.
Three times rent is the most common, but some landlords use 2.5x in higher-cost markets or 3.5x for premium units. Choose a multiple that fits your market and apply it consistently to every applicant to keep your screening fair and defensible.
Most landlords apply the multiple to gross income, the amount before taxes and deductions, because it is easy to verify from pay stubs or offer letters. Be clear in your criteria about which you use so applicants know how they will be evaluated.
No. Income affordability is one part of screening. Landlords also review credit, rental history, references, and employment stability. The income multiple sets a baseline; the other factors fill in whether the applicant is likely to pay reliably and care for the unit.