About the Rent Affordability Calculator
Rent is usually the biggest monthly cost, and choosing a place you can afford makes everything else easier. The classic rule says to spend no more than 30 percent of your gross income on housing. This calculator applies that rule and several variations to your income, shows the rent at 25, 30 and 35 percent, and takes your existing debt payments into account. If you have a specific rent in mind, it tells you what share of your income it takes and how much yearly income landlords may ask for, since many require an income of about 40 times the monthly rent.
Updated October 2026
How to use the Rent Affordability Calculator
- 1Enter your monthly income before tax.
- 2Enter your monthly debt payments.
- 3Choose the share of income you want to spend on rent.
- 4Optional: enter a rent you are considering.
- 5Read the maximum rent and the checks against your debts.
Worked example
With an income of 4,500 a month and debts of 400, the 30 percent rule gives 1,350 of rent. At 35 percent, it would be 1,575. A rent of 1,500 would take 33.3 percent of income, and with debts the total is 42.2 percent, just under the 43 percent limit that lenders often use. The landlord's 40 times rule would ask for 60,000 a year, which is above 54,000 you earn, so you might need a guarantor.
If you are sharing, run the numbers for the whole household and then divide by each person's share of the income, not equally, so that someone who earns less is not stretched. Landlords often check each tenant against the rent split, and may ask for a guarantor when one person falls short. Agree on how to handle bills, deposits and a notice period before you sign, so everyone knows what they are committing to.
Beyond the rule
- Add utilities, internet, insurance and transport.
- Keep money aside for the deposit and moving.
- Check the lease for rent increases.
- Think about commute costs.
- Make sure you can still save for emergencies.
Negotiating and saving
Rent is often negotiable, especially for longer leases or in slow seasons. Sharing with a flatmate, choosing a smaller place or moving a few stops down the train line can lower the cost by hundreds a month. Put the difference into savings, and your housing choice will help your finances instead of squeezing them.
Related tools
The Rent vs Buy Calculator compares renting with owning, the Budget Calculator maps out your monthly spending, the Debt-to-Income Calculator tests your ratio and the Emergency Fund Calculator helps you plan a cushion.
Features
- Maximum rent at your chosen share
- Quick view at 25%, 30% and 35%
- Debt-adjusted limit
- Rent as a share of income for a specific flat
- Income landlords may require
- Any currency
Frequently asked questions
How much rent can I afford?
A common guide is 30 percent of your gross monthly income. On 4,500 a month, that is 1,350. If you have large debts, aim lower, because rent plus debt payments should stay under about 43 percent of income.
What is the 40x rent rule?
Many landlords and agents ask for a yearly income of at least 40 times the monthly rent. For 1,500 a month, that is 60,000 a year. Some accept a guarantor or extra deposit if you fall short.
Should I use gross or net income?
The 30 percent rule uses gross income, before tax. If you prefer to base it on take-home pay, a common alternative is 35 to 40 percent of net income, which gives a similar result.
Do utilities count as rent?
They are separate in the rule, but you should include them in your budget. If utilities are not included, add 100 to 300 a month depending on the size of the home and the local climate.
What if I live in an expensive city?
Many people pay more than 30 percent in high-cost areas. If you do, cut other costs, consider sharing, or look further out. Check that you can still save, since a higher rent leaves less room for emergencies.
Is the rule the same everywhere?
The 30 percent rule comes from US housing policy and is used as a rough guide in many countries. Local rental markets, taxes and incomes vary, so treat it as a starting point.