Connected TV (CTV) is one of the fastest-growing areas in digital advertising. As more consumers cut the cord and shift their viewing habits from traditional broadcast and cable to streaming platforms, the way brands reach and influence audiences is evolving fast. Today, millions of viewers access content through smart TVs, streaming sticks, gaming consoles, and connected devices, and advertisers are following them.

But simply reaching audiences on CTV isn't enough. The real power lies in how campaigns are measured and optimized. For brands to make the most of this channel, they need to go beyond impressions and views. Success depends on understanding which metrics matter, how performance varies by format and audience, and what data can be used in-flight to improve outcomes.

In this article, we’ll cover what CTV is, how advertising works on these platforms, and the most important metrics brands need to track to ensure results.

What Is Connected TV Advertising?

CTV advertising is the placement of video ads on internet-connected television devices. Devices include Smart TVs, streaming devices like Roku, Apple TV, or Amazon Fire TV Stick, and gaming consoles such as Xbox or PlayStation. 

It allows advertisers to reach viewers who consume content on demand, outside the traditional broadcast or cable ecosystem.

CTV advertising is typically bought and sold programmatically, meaning ads are delivered using data and automation to target specific audiences. What sets it apart is interactivity: viewers can click through an ad to a website or app. That means it’s not just about awareness, but also about action.

And unlike traditional TV, CTV gives marketers access to real-time performance data.

Why Measurement Matters in CTV

CTV combines the best of the small screen with the trackability of digital. But to make it work, brands need to pay close attention to how they measure success.

Strong measurement helps you:

• Understand which audiences are responding
• Prove return on investment (ROI)
• Improve campaigns in real time
• Justify spend to internal stakeholders

Let’s explore the most important CTV metrics in more detail.

Key CTV Metrics and What They Mean

1. Video Completion Rate (VCR)

What it is: The percentage of viewers who watch your video ad from start to finish.

Why it matters: CTV ads are typically non-skippable, which means high VCRs signal strong ad delivery and attention. A consistently high VCR suggests that your creative is resonating and your audience is staying engaged.

How it’s measured: Tracked through ad servers or platforms. VCRs on CTV often exceed 90%, making it a reliable indicator of viewer attention.

2. Brand Lift

What it is: A measurement of how much your campaign increased brand awareness, consideration, or intent to purchase.

Why it matters: Brand lift tells you whether your campaign changed perception or behavior. It's especially useful for top-of-funnel or awareness-based strategies.

How it’s measured: Typically measured via surveys comparing responses from two groups: an exposed group (saw the ad) and a control group (did not see the ad). A positive difference between these groups indicates lift.

3. Return on Ad Spend (ROAS)

What it is: The revenue generated for every pound or dollar spent on CTV advertising.

Why it matters: ROAS connects your campaign to real business outcomes. It’s one of the clearest ways to demonstrate impact and justify future investment.

How it’s measured: Use pixel tracking, post-view conversions, or compare revenue and traffic uplift before and after campaign periods. Attribution models help map conversions back to CTV exposure.

4. Cost per Completed View (CPCV)

What it is: The average amount you pay when a viewer watches your video ad through to the end.

Why it matters: CPCV is a strong cost-efficiency metric. A low CPCV combined with a high VCR indicates your campaign is cost-effective and reaching the right audience.

How it’s measured: Calculated by dividing total campaign spend by the number of completed video views.

5. Reach and Frequency

What it is: Reach is the number of unique individuals who saw your ad. Frequency is how many times, on average, each person saw it.

Why it matters: A balanced reach and frequency strategy helps build awareness without overwhelming users. Underexposure may limit effectiveness, while overexposure can lead to wasted spend or ad fatigue. The optimal frequency for CTV often falls between 8–14 exposures.

How it’s measured: Ad platforms and measurement partners aggregate this data by user IDs or households and report it as part of campaign performance dashboards.

6. View-Through Rate (VTR)

What it is: The percentage of users who completed watching the video ad compared to those who started it.

Why it matters: While similar to VCR, VTR is more relevant on platforms where ads can be skipped or exited. It helps assess how compelling your content is, particularly when completion isn’t guaranteed.

How it’s measured: Tracked by the video player or ad server. Calculated by dividing the number of completed views by total impressions or starts.

7. Incremental Reach

What it is: The percentage of viewers reached exclusively via CTV who were not reached by other channels, such as linear TV or digital display.

Why it matters: It helps prove CTV’s added value in your media mix, showing how the channel contributes to broader campaign goals like unduplicated reach or new audience exposure.

How it’s measured: Requires cross-channel deduplication using third-party measurement tools or identity resolution partners. Platforms may compare CTV exposure against a baseline group exposed only to other formats.

8. Engagement Rate (for Interactive CTV Ads)

What it is: The percentage of viewers who interacted with your ad, whether it’s clicking a button, tapping a remote, scanning a QR code, or taking another action.

Why it matters: For campaigns aiming to drive action, engagement rate is key. It shows how well your creative prompts users to do something beyond passive viewing.

How it’s measured: Tracked through interactive ad platforms. Measured by dividing total interactions by total impressions. 

How Real-Time Measurement Drives Better Results

Traditional TV offers limited visibility on who saw your ad or what happened after. CTV changes that. With tools like Brand Lift Live by QuantcastTM, advertisers can:

• Measure brand awareness and consideration in real time
• Break down performance by audience, device, format, and creative
• Adjust spend mid-campaign to double down on what’s working

Case Study: How Pandora Used CTV to Unlock New Audiences

To expand its market share and reach new audiences beyond traditional TV, Pandora partnered with Carat and Quantcast to launch a connected TV (CTV) campaign targeting streaming audiences. 

Using Quantcast’s audience curation platform, they built custom segments focused on viewers of award shows and reality TV. The campaign successfully reached cord-cutting consumers on smart TVs, gaming consoles, and streaming devices. 

As a result, Pandora gained highly engaged new customers and outperformed industry benchmarks, reducing cost per completed view (CPCV) by 50%. The strategy helped strengthen brand connection using sight, sound, and motion while driving measurable business growth.

Advantages of CTV Advertising

CTV helps advertisers engage the growing number of users who don’t watch traditional TV. These audiences are often younger, tech-savvy, and harder to reach elsewhere. With real-time data, advertisers no longer have to guess. They can prove effectiveness and optimize spend across campaigns. CTV is no longer just for awareness. With clickable ads and advanced tracking, brands can drive conversions, not just impressions.

CTV is transforming how brands connect with audiences. But the real power lies in how you measure it. From video completion rates to return on ad spend, having the right metrics in place helps advertisers move from visibility to value.

Whether you're looking to build awareness or boost sales, connected TV advertising gives you the tools to track, optimize, and grow, all in real time.