What budget do you need to start on Google Ads?

A budget you can spend for several weeks without return, while the campaigns learn. The amount depends on the price of your products and the cost of clicks in your sector.

Performance Max or a standard Shopping campaign?

Performance Max runs across all Google placements from the product feed, with few settings. A standard Shopping campaign leaves more control over bids and search terms. Many stores start with one and test the other afterwards.

How long before you can judge a campaign?

Not before several weeks and a sufficient number of conversions. Changing a campaign every two days restarts its learning and prevents any conclusion.

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Google Ads for an online store: where to start

By the Banzai Labs teamUpdated on November 11, 20263 min read

Before paying for a click

Advertising does not fix a store that does not sell. It sends more people to the same flaws. Three prerequisites:

The store already converts. Sales come in through search, social or word of mouth.
Measurement is reliable. The purchase event comes through with the right amount. See our e-commerce tracking guide.
The product feed is approved by Merchant Center, with no disapprovals.

This is the base the Soporifik and Small Eden campaigns run on.

Work out what a sale can cost

It is the calculation most often skipped, and the only one that says whether a campaign is profitable.

Start from the average order value, excluding tax.
Subtract the cost of goods, shipping, payment fees and returns.
What remains is the margin per order. It is the ceiling of what you can pay to win that order.

From it you get the minimum return on ad spend (ROAS): revenue excluding tax divided by margin. A store that keeps a 25% margin before advertising must make at least 4 euros in sales for every euro spent, just to break even.

What a sale can cost

Average order, excl. tax
−
CostsProducts, shipping, payment fees, returns.
=
Margin per orderThe ceiling on what an order can cost.

25%Margin before advertisingExample store.
× 4Minimum ROASAt least 4 euros in sales for every euro spent, just to break even.

The campaigns that matter for a store

Shopping and Performance Max. They rely on the Merchant Center feed. The ad is the product listing: photo, title, price. Feed quality is therefore campaign quality.

Brand search. When someone types your name, you must come first. These clicks are cheap and protect you from competitors bidding on your brand.

Non-brand search. Text ads on queries that express purchase intent. More expensive, slower to tune, to open second.

Remarketing. Ads for people who viewed a product or filled a cart without ordering. It requires properly collected consent.

Start small

One product campaign, with the best sellers and the best margins.
A single conversion goal: the purchase.
A modest daily budget, held for several weeks without touching it.
Product titles rewritten with the words customers type.

What we look at every week

Search terms. Unrelated queries become negative keywords.
Products. Those that spend without selling leave the campaign or move to a separate one.
Cost per purchase, compared with the margin calculated above.
Landing pages. A slow or confusing product page wastes the best-targeted clicks.

The expensive mistakes

Launching without purchase tracking, and optimising for clicks.
Counting conversions twice, through GA4 and through the Google Ads tag.
Mixing brand and non-brand in one campaign. Good brand numbers hide losses elsewhere.
Judging on reported ROAS without looking at margin.
Stopping everything after ten days.

And then

When a campaign is profitable, we raise its budget in steps and open the next channel. Advertising remains an amplifier. Search, email and product page quality are the foundation, and they do not stop when the budget stops.

Frequently asked questions

What budget do you need to start on Google Ads?: A budget you can spend for several weeks without return, while the campaigns learn. The amount depends on the price of your products and the cost of clicks in your sector.
Performance Max or a standard Shopping campaign?: Performance Max runs across all Google placements from the product feed, with few settings. A standard Shopping campaign leaves more control over bids and search terms. Many stores start with one and test the other afterwards.
How long before you can judge a campaign?: Not before several weeks and a sufficient number of conversions. Changing a campaign every two days restarts its learning and prevents any conclusion.