Which metric would best indicate the overall effectiveness of an ad campaign aimed at generating leads?

The metric that best indicates the overall effectiveness of an ad campaign aimed at generating leads is the conversion rate. This is because the conversion rate specifically measures the percentage of users who take the desired action after engaging with the ad, such as signing up for more information, downloading a resource, or completing a form. In the context of lead generation, the ultimate goal is to convert viewers into leads, making the conversion rate a direct reflection of how well the ad campaign is performing in achieving this objective.

While total impressions indicate how many times the ad has been viewed, they do not provide insights into the quality of those views or whether they resulted in engagement or lead generation. Engagement rate, which looks at interactions like clicks, shares, or comments, is more focused on interest but does not explicitly measure lead conversion. Cost per thousand impressions (CPM) assesses the efficiency of ad spending based on reach but offers no insights into whether that reach is translating into actual leads. Therefore, conversion rate is the most relevant metric for evaluating the success of a campaign specifically designed to generate leads.