An advertiser looking to drive conversions is using manual cost-per-click (CPC) bidding. Which factor should be most important for this advertiser when deciding keyword bids?
Correct Answer
The profit derived from a paid click
Why is this the correct answer?
When using manual CPC bidding to drive conversions, the most important factor for deciding keyword bids is the profit derived from a paid click. This is the true ROI metric — it accounts for conversion rate, average order value, and profit margin together. If a keyword generates clicks that convert at 5% and each conversion is worth £50 profit, the maximum profitable CPC is £2.50. Setting bids based on profit per click ensures ad spend never exceeds what the business can profitably pay, making campaigns both competitive and financially sustainable.
Why are the other options incorrect?
The bids of the next closest advertiser
The next closest competitor's bids tell you what to pay to win the auction, but not whether winning that auction is profitable. Bidding based solely on competitors can lead to overspending on low-value clicks.
The average profit per conversion
Average profit per conversion is a useful starting point but does not account for conversion rate — a high average profit with a very low conversion rate may still mean the CPC bid is unprofitable.
The Quality Score of the keyword
Quality Score affects Ad Rank and CPC efficiency, but it does not directly determine what bid level is financially justified for a given keyword.
Real-World Example
A travel agency calculates that holiday bookings have a £300 average profit and a 4% conversion rate from paid clicks. Maximum profitable CPC = £300 x 4% = £12. They set keyword bids at £10 to maintain a 20% margin of safety. This profit-derived bidding approach generates consistent positive ROI across all campaigns.