What Google Ads budget to plan when you sell to consumers

"How much should I put on Google?" The question is asked the wrong way round. A budget is not a number you pick, it is a result: it follows from the number of enquiries you want and what a click costs in your trade and area.

How Google spends your budget

On Google Ads, you set an average daily budget. Google can spend up to twice that amount on a day with lots of searches, and makes up for it on quieter days. Over a month, it does not exceed about 30.4 times your daily budget, the average number of days in a month.

In practice: €30 a day gives at most just over €900 a month, but some days at €60 and others at €10. That is not a bug, it is how it is designed.

The sum, worked backwards

Three numbers are enough.

1. The number of enquiries you want per month. The ones your team needs to sign what you are aiming for.
2. Your page's conversion rate. The share of visitors who send an enquiry.
3. The cost per click of your keywords. Google's keyword planner gives an estimate by area.

Monthly budget = enquiries wanted ÷ conversion rate × cost per click.

With round numbers, purely as an example: 20 enquiries wanted, a page that converts 5% of visitors, a €3 click. You need 400 clicks, so €1,200 for the month. Change any one of the three and the budget follows: a page that converts 10% halves the bill.

That is why I look at the landing page before touching the budget. What makes a page convert.

The floor: enough data to learn

Google's automated bidding strategies, the ones that target a cost per conversion, need conversions to learn. With two enquiries a month, the algorithm has nothing to hold on to, and results stay erratic.

A budget that is too small is not a scaled-down version of a good budget: it is often a campaign that never learns. One well-fed campaign on your most profitable keywords beats five campaigns on a few euros a day.

What pushes the cost per click up or down

• Local competition. The more advertisers on "heat pump" in your town, the higher the auction.
• Ad and page quality. Google rewards relevance: an ad that matches the search and a page that answers it pay less for the same position.
• Keywords that are too broad. They bring clicks that will never become customers. A negative keyword list rules them out.

The number to follow next

Once the campaign is live, the budget is steered by cost per enquiry, then by cost per signed customer. The cost per click is just an ingredient. How to calculate cost per lead and, further on, the cost of a signed job.

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Further reading: SEA: definition and difference with SEO and What Meta Ads budget to plan, the same reasoning on Facebook and Instagram.

Want a number for your case? Book a 30-minute call. We do the sum together with your keywords, your area and your average sale.