Google's one-to-ten rating of how relevant your keyword, your ad and your landing page are to each other and to what the searcher typed. It is calculated per keyword and directly affects what you pay.
Quality Score is why a smaller advertiser can outrank a larger one. Google does not simply sell the top position to the highest bidder — it multiplies the bid by a quality measure, so relevance buys position that money would otherwise have to.
It breaks into three parts, each shown in the interface: expected click-through rate, ad relevance, and landing page experience. One of the three is normally doing all the damage, and it is usually the landing page.
| Expected CTR | Below average | The ad is not answering the search |
|---|---|---|
| Ad relevance | Below average | The keyword does not appear in the ad |
| Landing page experience | Below average | Ads point at the homepage, or the page is slow |
There is a free calculator on this site for exactly this.
A free consult is twenty minutes and there is no pitch deck at the end of it.