How this Google Ads budget calculator works

Most businesses pick an ad budget by gut feel. This planner does the opposite: it starts from the revenue you want and works backwards through your sales funnel, so the budget is tied to an outcome.

Worked example

A home improvement company wants $50,000 a month from Google Ads. Jobs average $5,000, so it needs 10 customers. Closing 25% of leads means 40 leads. At an 8% landing page conversion rate that's about 500 clicks, and at roughly $8 per click the monthly budget lands around $4,000.

What is a good ROAS for Google Ads?

There's no universal number. A good ROAS is one that clears your break-even point with room to spare. With a 40% gross margin you break even at 2.5x; with a 70% margin you break even at about 1.4x. The calculator shows both, so you can see how much headroom you have.

Why spend less in month one?

Fresh campaigns go through a learning phase. Smart Bidding needs conversion data, search terms need pruning, and ads need testing. Clicks usually cost more and convert worse during this period, so the 90-day plan starts slightly below full budget, then scales once the account has data.

How to lower the budget you need

• Raise your landing page conversion rate. Moving from 4% to 8% halves the clicks you need for the same leads.
• Follow up faster. Close rate is the most overlooked lever. Calling leads within minutes typically lifts it noticeably.
• Cut wasted spend. Negative keywords, tighter location targeting and ad scheduling bring average cost per lead down.
• Track real outcomes. Feed booked calls and closed deals back into Google Ads so bidding optimises for customers, not form fills.

Frequently asked questions

How much should a small business spend on Google Ads?

Enough to buy the clicks your goal requires. If the budget this calculator gives you is too high, adjust the goal or improve conversion and close rates rather than spreading a small budget thin across too many keywords.

Where do the industry benchmarks come from?

The presets use median cost-per-click and conversion-rate figures from WordStream's 2026 Google Ads benchmarks, based on more than 13,000 US search campaigns. Your own numbers will vary by location, competition and landing page quality.

Does this work for Microsoft Ads or Meta Ads?

The funnel math is the same for any pay-per-click channel. Swap in that platform's cost per click and conversion rate.

Benchmark source: WordStream / LocaliQ, Google Ads Benchmarks 2026 (median US search campaign data, Apr 2025 – Mar 2026). Estimates only; results vary.