Google Ads Metrics Glossary: CTR, CPC, Conversions and ROAS

Core metrics explained so you can tell whether campaigns make money or burn budget.

Impressions

Counted each time your ad is shown. Not a click — only a chance to be seen.

(Clicks ÷ Impressions) × 100. Measures how compelling ad and keyword are together.

CPC from the auction and Quality Score. Conversion = action you define. CPA = cost ÷ conversions. ROAS = value ÷ spend.

What is a good CTR in Google Ads?

It depends on the industry. Use your account history as the baseline.

Is ROAS more important than CPA?

For e-commerce with reliable values, ROAS is often clearer.

Why is my ROAS unreliable?

Broken tags, missing values, or delayed attribution. Fix measurement before optimising bids.

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