Facebook Ads vs Google Ads for E-Commerce: Where Should You Spend?

If you sell products online, you've almost certainly considered running ads on Facebook (Meta) and Google. Together, these two platforms command over 50% of global digital ad spend — and for good reason. They offer the most sophisticated targeting, the largest audiences, and the most mature optimization algorithms in the industry.

But they work in fundamentally different ways. Google Ads captures intent — people actively searching for products. Facebook Ads creates demand — putting your products in front of people who haven't searched for them yet but match your ideal customer profile.

Understanding this distinction is the key to deciding where to allocate your budget. Most successful e-commerce stores eventually use both, but the optimal split depends on your product type, price point, margins, and growth stage.

Google Ads puts your products in front of people at the moment they're actively looking to buy. When someone types "best running shoes for flat feet" into Google, they're deep in the purchase funnel — they've already identified their problem and are researching solutions.

The main Google Ads formats for e-commerce are:

• Google Shopping: Visual product listings that appear at the top of search results with images, prices, and store names. Shopping ads typically deliver the highest ROAS of any ad format because they show to people with strong purchase intent.
• Search Ads: Text-based ads that appear for specific keywords. Effective for branded searches and high-intent product queries.
• Performance Max: Google's AI-driven campaign type that runs across Search, Shopping, YouTube, Display, and Gmail. It's a black box — you provide assets and Google optimizes delivery.

Average metrics for e-commerce:

• Average CPC (cost per click): $1.16 for Shopping, $2.69 for Search
• Average conversion rate: 2.81% for Shopping, 1.91% for Search
• Average ROAS: 3.1x–5x for Shopping campaigns

Google's biggest advantage is that you're meeting customers where they already are in the buying journey. The downside is higher competition and CPCs for popular product categories, and limited ability to create demand for new or unknown products.

Facebook (Meta) Ads takes the opposite approach. Instead of waiting for people to search, Facebook proactively shows your products to users whose behavior, demographics, and interests suggest they're likely to buy. This is demand generation — creating desire for your product before the customer even knows they want it.

Facebook's key advertising strengths include:

• Lookalike Audiences: Upload your customer list and Facebook finds users who share similar characteristics. This is one of the most powerful prospecting tools in e-commerce advertising.
• Visual storytelling: Video ads, carousel ads, and collection ads let you showcase products in lifestyle contexts that create emotional connections.
• The Meta ecosystem: Your ads can run across Facebook, Instagram, Messenger, and the Audience Network — reaching over 3 billion monthly active users.
• Retargeting power: The Meta Pixel tracks website visitors, allowing you to show specific product ads to people who viewed a product but didn't buy.

Average metrics for e-commerce:

• Average CPM (cost per 1,000 impressions): $11.54
• Average CPC: $1.72
• Average conversion rate: 1.82%
• Average ROAS: 2.5x–4x for well-optimized campaigns

Facebook excels at top-of-funnel awareness and mid-funnel consideration. It's particularly effective for visually appealing products, impulse purchases under $50, and brands with a compelling story to tell.

Let's compare the two platforms across the dimensions that matter most for e-commerce merchants:

Neither platform is universally "better." The ideal choice depends on your specific situation — and for most established stores, the answer is both, with budget weighted toward whichever delivers better ROAS for your product category.

Start with Google Ads if:

• People are actively searching for your product category (e.g., "organic dog food," "wireless earbuds")
• Your product solves a specific, well-known problem
• You have competitive pricing and strong product images for Shopping ads
• You want the highest immediate ROAS with less creative effort

Start with Facebook Ads if:

• Your product is visually compelling and benefits from lifestyle imagery or video
• You're launching a new or innovative product that people don't know to search for yet
• Your price point is under $50 and suited for impulse purchases
• You have a strong brand story or unique angle that resonates in social feeds

Use both if: You're spending more than $3,000/month on ads, you've found product-market fit, and you want to capture demand at every stage of the funnel. A common strategy is to use Facebook for prospecting and awareness, then retarget interested users with Google Shopping and Search ads.

The biggest challenge with running ads on both Google and Facebook is cross-platform attribution. Both platforms will claim credit for the same sale if a customer interacts with ads on both before purchasing. This is known as the "double-counting" problem, and it can make your combined ROAS look artificially high.

To get accurate cross-platform performance data, you need a tool that:

• Connects to all your ad accounts in one place
• Matches ad spend against actual Shopify revenue (not platform-reported revenue)
• De-duplicates conversions so the same sale isn't counted twice
• Shows you blended ROAS and per-platform ROAS side by side

InsightIQ does exactly this. By connecting your Shopify store and all your ad platforms, you get a single dashboard that shows true, de-duplicated performance — so you can make confident budget allocation decisions based on real data, not inflated platform metrics.