How much should a small business spend on Google Ads?

A simple way to set a Google Ads budget from your cost per click, conversion rate and the number of leads you need.

By the WebsiteMatrixs team · Updated 2026-10-30 · 5 min read

There's no single right budget, but there is a simple way to work one out from three numbers.

The formula

Leads per month = budget ÷ cost per click × conversion rate. If clicks cost $5 and 6% of visitors become leads, $3,000 a month buys about 600 clicks and 36 leads, or roughly $83 per lead.

Where to get the numbers

Cost per click: Google's Keyword Planner shows bid ranges for your keywords and area.
Conversion rate: use your own landing page data if you have it; otherwise start with a conservative estimate.
Lead value: how many leads become customers, and what a customer is worth to you.

Start focused

A small budget spread across many keywords and cities gets too little data to optimize. Start with your most profitable service in your best area, prove the cost per lead, then expand.

Try the calculator on our Google Ads page to test your own numbers.