CPC went up: is it your own bids or the competition?

You meet it in the average cost per click figure: it steps up, and the question is whether something in the account moved it or something in the auction did.

In the self-inflicted case, the step sits at the date of an edit the account made to itself: a campaign's location targeting narrowed, or its keywords narrowed, with the budget left where it was. That is why change history is the first thing to open.

Google describes Maximise conversions as setting bids to help get the most conversions for your campaign while spending your budget, and says it will try to fully spend your average daily budget. Narrow the targeting, keep the budget, and if the same spend buys fewer clicks, the average cost per click has to rise. No rival is needed for that arithmetic.

The two causes then separate in the share columns. Impression share is impressions divided by the impressions Google estimates you were eligible for. In the self-inflicted case your own impression share and search top impression share go up. Under real competitive pressure they go down, and the auction insights report shows it: a rival's overlap rate, how often their ad showed when yours did, and position above rate, how often theirs sat higher when both showed, both climb.

The cost is the wrong fix. A self-inflicted cost per click rise blamed on competitors, the season or the landing page sends the fix to the wrong place, and none of those touches the edit that actually moved the price.

It also corrupts the comparison. The period before the narrowing and the period after it are two different sets of auctions, so a before and after cost per click across that step compares unlike things. Where the narrowing was to locations, hold geography constant and compare the same regions on both sides.

Read it in order. Check change history at the date of the step for location, keyword, budget and bid strategy edits. Put spend, clicks, impression share and search top impression share side by side for the periods before and after. Then open auction insights for overlap and position above rate. Google notes the report shows nothing when your impression share is under 10%, and that impression share is an estimate whose set of counted auctions can shift when your bids change, so a small move is a prompt to look, not a verdict.

It is not a reading for Target CPA. Google says Target CPA sets bids for each auction to achieve the average target you set, rather than spending your full budget to maximise conversions. The flat spend this pattern starts from is not what that strategy aims at, so a cost per click rise there needs its own read.

Nor is it a Lost IS (budget) reading. Google says it does not recommend the Lost IS (budget) column with Maximise conversions, because the strategy is designed to spend the full daily budget and is limited by budget by design, and the column does not account for that. A high reading there is not evidence of what moved your cost per click.