What is the 30% rule for rent?

A common guideline is that rent should be no more than 30% of your gross monthly income. Spending more can leave too little for other costs, though it varies by city and lifestyle.

How accurate are these figures?

The maths is exact — affordable rent is 30% of gross monthly income, percentages are rent divided by income, and the 40x screen is rent times 40 compared with your annual income. The 30% and 40x figures are widely used rules of thumb, not legal limits, so treat them as guidance.

Is my income data sent anywhere?

No. The calculator is privacy-first — your income and rent figures stay in your browser and are never transmitted or stored.

Rent Affordability Calculator

Rent affordability calculator

How much rent can you comfortably afford? This calculator checks your rent against two common benchmarks: the 30% rule (rent should be at most 30% of gross monthly income) and the 40× screen many letting agents use (annual income of at least 40 times the monthly rent).

Enter your gross annual income, net monthly pay, rent and other debts, and the tool shows the affordable rent, what proportion of income rent consumes, what’s left over each month and whether you pass the 40× check. It is privacy-first: nothing leaves your browser.