What Is a KPI? Key Performance Indicators Explained

What is a Key Performance Indicator?

A Key Performance Indicator (KPI) is a quantifiable metric that helps you track progress toward your most strategic advertising and business goals. In the world of digital advertising, especially programmatic, KPIs offer a clear view into what’s working, what’s lagging, and where you can optimize.

Think of KPIs as your campaign’s north stars. They align your media spend with your business outcomes, helping you stay focused on impact rather than vanity metrics. Whether you’re evaluating creative effectiveness, media efficiency, or conversion behavior, KPIs help translate campaign activity into business insight.

At Agility, KPIs are at the heart of performance-focused, resolution-minded strategy. They're how we stay accountable to results and help our clients scale with purpose.

What Does "Key Performance Indicator" Mean?

The word “key” is doing a lot of heavy lifting here. While you may track dozens of data points in a campaign, KPIs are the ones that matter most. These indicators are directly tied to the goals that define success for your team or client, whether it’s increasing ROAS, lifting brand engagement, or improving cost-per-acquisition.

Importantly, KPIs aren’t static; they evolve alongside your campaign objectives and media mix. They also differ depending on whether you're tracking leading indicators (predictive signals, like page visits or audio ad plays) or lagging indicators (outcomes, like conversions or closed deals).

Key Performance Indicator Examples in Advertising

Here are a few KPI examples that are especially relevant in programmatic advertising across formats like display, video, audio, and CTV:

Performance KPIs

• Click-Through Rate (CTR) – Measures how many people clicked your ad after seeing it.

• Conversion Rate – Tracks how many people took a meaningful action (purchase, signup) after engaging.

• Cost Per Acquisition (CPA) – Shows how efficiently you're turning budget into results.

Brand Awareness KPIs

• Viewability Rate – Reflects how often your ads were actually seen by users.

• Completion Rate (Video/Audio) – Measures how often your ad was watched or heard to the end.

• Brand Lift – Gauges change in brand awareness or consideration, often via surveys or A/B testing.

Customer-Centric KPIs

• Customer Lifetime Value (CLV) – Projects the total value a customer brings over time.

• Retention Rate – Indicates how many customers return after their initial interaction or purchase.