Quality Score is Google's rating of the relevance and quality of your keywords, ads, and landing pages. It's scored on a scale of 1 to 10, and it has a direct impact on both your ad rank and your cost per click. A higher Quality Score means you pay less for the same position - and a lower one means you're paying a premium to compete.
The score is made up of three components: expected click-through rate, ad relevance, and landing page experience. Google evaluates each of these relative to other advertisers targeting the same keyword, so it's always a comparative measure - not an absolute one.
Expected click-through rate is Google's prediction of how likely your ad is to be clicked when shown for a given keyword. This is based on historical performance data and is heavily influenced by how well your ad copy speaks to the search intent behind the keyword. Ads that match what the searcher is actually looking for get clicked more - and Google rewards that.
Ad relevance measures how closely your ad copy matches the keyword it's targeting. A common mistake is writing one generic ad and applying it across dozens of keywords. The fix is tighter ad groups - grouping closely related keywords together and writing ad copy that speaks directly to each group.
Landing page experience is often the most neglected component. Google evaluates whether your landing page is relevant to the ad, loads quickly, is mobile-friendly, and provides a good user experience. Sending traffic to a generic homepage instead of a dedicated landing page is one of the fastest ways to tank your Quality Score.
To improve your Quality Score, start with your lowest-scoring keywords. Tighten your ad groups so each one covers a narrow theme. Rewrite your ad copy to include the keyword naturally and speak directly to the search intent. Then audit your landing pages - make sure they're fast, mobile-optimized, and directly relevant to what the ad promises. Small improvements across all three components compound quickly.