How to Optimise Google Shopping: A Specialist's Playbook

To optimise Google Shopping, work in this order. Fix your product feed first, because the feed is your keyword list and your advert copy. Then make sure conversion tracking reports the true value of each sale. Then structure campaigns around margin and performance, bid to a return on ad spend (ROAS) you can actually afford, and prune wasted search terms and dead products every week. Most underperforming Shopping accounts fail on the first two steps, not on bidding.

That order matters. Bid changes on a messy feed or broken tracking just help Google spend money faster on the wrong things. This guide walks through each stage as we would approach it on a real account: what to check, what to change, and how to judge whether it worked. It assumes your Shopping campaigns already exist. If they don't, start with our step-by-step guide to setting up Google Shopping in the UK and come back here.

Step 1: Treat your product feed as the campaign

In a normal search campaign you choose keywords. In Shopping you don't. Google reads your product data and decides which searches each product is relevant for. If a product title says "Classic Jacket", Google has very little to match against. If it says "Men's Waterproof Walking Jacket, Navy, Breathable Shell", it can match dozens of useful searches.

So the first stage of any Shopping optimisation is a feed audit. Open the Diagnostics section of Google Merchant Centre and go through the products tab before touching anything in Google Ads.

Fix disapprovals and warnings first

Disapproved products can't show at all, so they're the quickest win. Common causes include:

• Price or availability on the landing page not matching the feed
• Missing or invalid GTINs (barcodes) for branded products
• Images with promotional text, watermarks or borders overlaid
• Missing shipping or returns information in Merchant Centre
• Policy issues such as restricted products or unclear claims

Warnings don't stop products showing, but they often hold them back. Treat "limited performance" warnings about missing identifiers or weak data as part of the job, not as noise.

Rewrite product titles to match how people search

Titles are the single most important attribute you control. Google allows up to 150 characters, but shoppers usually see only the opening words, so the most important terms should come first. Build titles from a formula for each category rather than writing them one by one.

Category	Title formula	Example
Clothing	Brand + Gender + Product type + Key feature + Colour + Size	Hillmoor Women's Waterproof Walking Jacket, Navy, Size 12
Electronics	Brand + Model + Product type + Key spec	Brand X200 Wireless Earbuds, Noise Cancelling, 30 Hour Battery
Home and furniture	Brand + Product type + Material + Size + Colour	Oak Dining Table, Solid Wood, 180cm, Natural Finish
Spare parts	Brand + Part number + Product type + Compatibility	Brand 12345 Brake Pads, Front, Fits 2018 to 2022 Models
Food and drink	Brand + Product + Variant + Weight or volume	Highland Single Estate Coffee Beans, Medium Roast, 1kg

A few practical rules:

• Put the brand first only if people search for your brand. If you make your own products and nobody knows the name yet, lead with the product type instead.
• Use the words customers use, not internal names. If your stock system calls it "SKU 4471 Hero Tee", the feed shouldn't.
• Avoid promotional language such as "Free delivery" or "Best price". It isn't allowed and it wastes space.
• Don't stuff keywords. One clear, descriptive title outperforms a list of synonyms.

You don't need to change titles on your website to do this. A supplemental feed in Merchant Centre (a simple Google Sheet keyed on product ID) lets you override titles and other attributes for Shopping only. On larger catalogues, feed rules can build titles automatically from existing attributes.

Fill in the attributes most shops skip

Beyond titles, these attributes are worth the effort:

• Description: lead with the most useful facts (what it is, who it's for, key specs). Google uses it for matching, even though shoppers rarely read it in the ad.
• GTIN, MPN and brand: for branded goods, correct barcodes help Google recognise the exact product and group you with comparison results.
• Product type: your own category path, such as "Outdoor Clothing > Jackets > Waterproof". It also gives you a clean way to split campaigns later.
• Google product category: Google often assigns this automatically, but check it's sensible, especially for unusual products.
• Colour, size, material, gender, age group: required for some categories and helpful for matching in all of them.
• Additional images and lifestyle images: the main image should be clean and clear, with extra images showing the product in use.
• Sale price and effective dates: so discounts show automatically and switch off on time.

Add custom labels for control

Custom labels (custom_label_0 to custom_label_4) are invisible to shoppers, but they're the most useful tool you have for structuring campaigns. Use them to tag products by things Google can't see:

• Margin band (high, medium, low)
• Price band (under £25, £25 to £75, over £75)
• Performance (best seller, average, no sales)
• Season or range (summer, Christmas, clearance)
• Stock depth (plenty, low stock)

Without custom labels, you'll end up structuring campaigns by whatever category your website happens to use. That rarely matches how you make money.

Step 2: Make sure tracking tells the truth

Every optimisation decision later in this guide depends on conversion data. If that data is wrong, your bidding strategy will confidently optimise towards the wrong outcome.

Check these points:

1. Purchases are tracked with the actual basket value, not a fixed value of one per sale. Shopping bidding works on conversion value, so it needs real revenue.
2. Only purchases count as primary conversions in Shopping campaigns. Add to basket, sign-ups and page views can be recorded as secondary actions, but they shouldn't drive bidding.
3. Values are consistent. Decide whether you're reporting including or excluding VAT and shipping, and stick to it. Mixing the two makes ROAS targets meaningless.
4. Enhanced conversions are set up where you can, to recover some of the conversions lost to cookie restrictions.
5. Duplicates are removed. If your shop platform and Google Analytics both send purchase conversions into Google Ads, you may be counting each sale twice.

If you want to go further, you can send cost of goods data into Merchant Centre and use conversions with cart data. That lets Google Ads report gross profit by product rather than just revenue, which is far closer to what you actually care about.

Data volume matters too. Automated bidding needs enough conversions to learn from, and accounts with very few sales behave differently from busy ones. We cover the thresholds and what to do below them in how many conversions you need to optimise Google Shopping.

Step 3: Structure campaigns around how you make money

There are two campaign types that serve Shopping ads: Standard Shopping and Performance Max. Smart Shopping was replaced by Performance Max a few years ago, and Google now pushes Performance Max heavily.

Neither type is automatically better. They suit different situations.

	Standard Shopping	Performance Max
Where ads show	Shopping placements only	Shopping plus Search, Display, YouTube, Gmail and Discover
Search term visibility	Full search terms report	Search term insights, less detail
Bidding	Manual CPC or automated	Automated only
Control over negatives, devices, schedules	High	Limited
Best for	Tight budgets, low data, high control needs	Accounts with steady conversion volume and good tracking

Whichever you use, the structural principle is the same: group products that deserve different targets. If a product with a 15% margin and a product with a 60% margin sit in the same campaign under one ROAS target, one of them is being bid wrongly.

Proven structures worth considering

Don't over-split. Every extra campaign divides your conversion data, and automated bidding performs poorly when each campaign only gets a handful of sales. For a small shop, two or three well-chosen splits usually beat ten thin ones.

Performance Max specifics

If you run Performance Max, a few settings make a noticeable difference to control:

• Brand exclusions: stop Performance Max taking credit for people already searching your shop's name, who would probably have found you anyway.
• Listing groups: use them, together with custom labels, to control which products sit in which asset group.
• Feed-only campaigns: some advertisers run Performance Max with only the product feed and minimal creative assets to keep spend weighted towards Shopping placements. Google doesn't promise it will stay there, so check placement reporting.
• Account-level negative keywords: block irrelevant searches across the account, including Performance Max.
• Customer acquisition goal: if growing new customers matters more than repeat sales, this setting lets you bid more for new buyers.

Step 4: Bid to profit, not to a nice-looking number

Most Shopping accounts eventually run on Maximise conversion value with a target ROAS. The question that matters is what that target should be. That starts with your break-even ROAS.

Work out your break-even ROAS

Break-even ROAS is the point where ad spend equals your gross profit on the sale. The formula is simple: divide 1 by your margin.

Worked example: you sell a product for £100 (excluding VAT). The product, packaging and delivery cost you £60. Your gross profit is £40, a 40% margin. Break-even ROAS is 100 divided by 40, which is 2.5, or 250%. At a ROAS of 250% you've spent £40 on ads to make £40 of gross profit, so you've made nothing. Anything above that is profit, anything below is a loss on that sale.

Gross margin	Break-even ROAS	What it means
20%	500%	You need £5 of sales for every £1 of ad spend just to break even
30%	333%	£3.33 of sales per £1 spent to break even
40%	250%	£2.50 of sales per £1 spent to break even
50%	200%	£2 of sales per £1 spent to break even
60%	167%	£1.67 of sales per £1 spent to break even

This table is why margin-based campaign structure matters so much. A single ROAS target across a mixed catalogue will be too aggressive for some products and too generous for others.

Allow for lifetime value

Break-even on the first order isn't always the right target. If customers typically come back and buy again, as they often do with consumables, pet food or skincare, you may accept a lower ROAS on the first sale. If most customers buy once and never return, you need the first sale to be profitable. Be honest about which group your shop falls into.

Choosing a bid strategy by stage

1. New or low-data accounts: manual CPC in Standard Shopping, or Maximise clicks with a sensible cap, lets you gather data without handing control to an algorithm with nothing to learn from.
2. Once sales are coming in steadily: move to Maximise conversion value without a target, so Google can learn what a valuable sale looks like.
3. Once that has stabilised: add a target ROAS, starting close to what the campaign is already achieving, then tighten it gradually towards your profit goal.

Step 5: Control the searches you appear for

Because Shopping has no keywords, you control relevance by removing the searches you don't want. This is where a lot of wasted spend hides.

Review search terms weekly

In Standard Shopping, open the search terms report and sort by cost. Look for:

• Searches for products you don't sell (a "cordless drill" search landing on a drill bit)
• Research terms with little buying intent, such as "how to", "diy" or "ideas"
• Competitor brand names where you don't stock that brand
• Searches for "second hand", "used" or "free" if you only sell new
• Searches that clearly want a cheaper or more premium product than yours

Add irrelevant terms as negative keywords. Build shared negative lists so the same exclusions apply across campaigns. Be careful with broad negatives, though. Excluding "cheap" might also block "cheap walking boots" when that's exactly what you sell.

Performance Max gives less detail, but search term insights still show the themes driving traffic, and account-level negatives let you block what clearly doesn't fit.

Query sculpting with campaign priority

For Standard Shopping, there's an advanced technique worth knowing. When the same product sits in several Standard Shopping campaigns, the campaign priority setting (high, medium or low) decides which one serves. You can use this to send generic searches and specific searches to different bids:

• High priority, low bid: catches broad, generic searches such as "walking jacket". Add specific terms as negatives here.
• Medium priority, medium bid: catches more detailed searches such as "women's waterproof walking jacket".
• Low priority, high bid: catches brand and model-specific searches with strong buying intent.

It takes more management, but it gives you something Shopping otherwise lacks: different bids for different levels of intent on the same product.

Step 6: Improve what the shopper actually sees

Shopping is a comparison format. Your product sits next to competitors' products, with price, image and seller details side by side. Optimising bids won't overcome a listing that loses the comparison.

Price competitiveness

Merchant Centre's price competitiveness reporting shows how your prices compare with others selling the same products, where Google can match them via GTIN. If you're noticeably more expensive on key products, no amount of bid tuning will fix the click-through rate. You might adjust price, bundle in value (free delivery, extended warranty) or accept that those products are better promoted elsewhere.

Images

Your main image is the biggest visual factor in the listing. Use a clean, well-lit shot on a plain background, with the product filling most of the frame. Test alternatives through a supplemental feed and compare click-through rates, but always stay within Google's image policies.

Promotions, shipping and returns

• Merchant promotions show an offer link under your listing when you have a genuine discount code or offer.
• Shipping settings in Merchant Centre should be accurate and, where you can, show free or low-cost delivery clearly.
• Returns policy details help shoppers trust a seller they haven't bought from before.
• Product ratings and seller ratings add stars to listings once you have enough reviews through a supported review provider.

None of these are glamorous, but they affect whether a shopper picks you out of a row of near-identical products.

Step 7: Prune products and fix the landing pages

Every catalogue has products that cost money and never sell. Run a product-level report (in Google Ads, the products tab or the Shopping performance view) over a long enough window to be fair, typically 60 to 90 days for most shops.

Sort products into groups:

• Spend with no sales: check the landing page, price and title first. If those are fine, lower bids or exclude.
• Sales at a loss: ROAS below break-even. Move to a campaign with a stricter target or exclude.
• Profitable but limited: products hitting target but losing impressions to budget or rank. These deserve more budget.
• No impressions at all: often a feed problem (weak title, wrong category) rather than a bidding one.

Then look at where the click lands. The product page should load quickly on mobile, show the same price and stock status as the feed, and make it easy to add to basket. Slow pages, surprise delivery charges at checkout or forced account creation will undo good Shopping work.

Step 8: Don't ignore free listings and local inventory

The same Merchant Centre feed also powers free product listings across Google. They don't replace paid Shopping, but every improvement you make to your feed helps both. Check that free listings are switched on in Merchant Centre.

If you have a physical shop, local inventory ads and free local listings can show nearby shoppers that a product is in stock today. That depends on having your shop set up properly on Google, with an accurate Business Profile linked to Merchant Centre.

A practical optimisation routine

Optimisation isn't a one-off project. Here's the routine we'd suggest for a typical small shop.

How often	What to do
Weekly	Check Merchant Centre for new disapprovals. Review search terms and add negatives. Check budgets aren't limiting profitable campaigns.
Fortnightly	Review ROAS against targets by campaign. Make small target adjustments where performance is consistently above or below.
Monthly	Run a product-level review. Update performance custom labels (best seller, zombie). Rewrite titles on products with impressions but low clicks.
Quarterly	Revisit margins and break-even ROAS. Review campaign structure. Plan seasonal campaigns and budgets ahead of peaks.
Before peaks	Check stock levels feed through correctly, sale prices have the right dates and promotions are approved in advance.

The mistakes we see most often

How long does optimisation take to show results?

It depends on what you're fixing. Disapproval fixes can bring products back into the auction within days of re-review. Title improvements usually take a few weeks to show clearly, because Google needs time to re-evaluate matching and you need enough traffic to compare. Bidding changes on automated strategies need a settling period each time.

Be wary of anyone promising fast, guaranteed results. Shopping performance depends on your prices, competitors, stock and margins as much as on the account itself. Honest optimisation is steady, measurable improvement, not overnight transformation.

Should you do this yourself or get help?

Plenty of shop owners handle feed fixes and basic search term reviews themselves, and this guide gives you a solid process to follow. Where outside help tends to pay for itself is in the more technical areas: supplemental feeds and feed rules on large catalogues, tracking and profit data, query sculpting and keeping automated bidding on track without wasting budget.

If you're running Shopping alongside search campaigns, it's worth having one specialist look at the whole account, because Shopping and search often compete for the same searches. Our Google Ads management covers both. If you'd like an independent view of where your account stands first, request a free Google Ads audit and we'll show you what we'd change and why.

We work on a fixed monthly fee with no pay-on-results arrangements, so our advice isn't skewed towards spending more of your budget. You can see the options on our Google Ads pricing page, with management starting from £145/month. Every package includes DPOM Mission Control, our iPhone app, so you can check reports and live results on demand and reach your account manager directly (Android is coming soon).

Common questions about optimising Google Shopping

Is Performance Max better than Standard Shopping?

Not automatically. Performance Max can work well for accounts with steady sales and reliable tracking. Standard Shopping gives more control and transparency, which often suits smaller budgets, low-data accounts and shops that need tight control over search terms.

What is a good ROAS for Google Shopping?

There's no universal figure. A good ROAS is one above your break-even point that leaves the profit you need. Work it out from your margins using the formula above, rather than comparing with other businesses.

Do I need to change my website to optimise my feed?

Usually not. A supplemental feed or feed rules in Merchant Centre can override titles, descriptions and custom labels for Shopping only, leaving your website untouched.

How many products should I advertise?

Start by advertising everything that's in stock and profitable to sell, then use performance data to cut or separate the products that don't pay their way. Excluding products before you have data risks hiding future best sellers.

Can optimisation guarantee more sales?

No. Nobody can guarantee results from Google Shopping, because so much depends on pricing, competition and demand. What good optimisation does is remove waste and put your budget behind the products and searches most likely to be profitable.