How much should you spend on Google Ads?
Work backward from customers, not from a number someone picked. Change the inputs to match your business: close rates, conversion rates and click costs vary widely by industry and city.
The formulaMonthly budget = customers wanted ÷ close rate ÷ landing-page conversion rate × average cost per click.
Example: 20 new customers a month, a 30% close rate, an 8% landing-page conversion rate and a $6 average click need about 67 leads and 833 clicks: roughly $5,000 a month, or $250 per customer.