Research Digest

Ad Length Impact on Attention is Minimal, But Content Tips the Scales


  • Roughly a third of viewers equally pay attention to 15, 30, and 60-second ads
  • Shorter ads are more ‘attentionally efficient’ and drive a higher uplift in either recall or choice
  • Six-second ads deliver 60% of a thirty-second ad’s impact, and can work in tandem with 15 or 30 second CTV  spots to boost impact.

Studies reveal that 47% of the value of a video campaign is delivered within the first three seconds—but this is only the beginning.

% of Viewers Who Paid Attention

Viewer Attention is Equally Weighted Across 15, 30 and 60-Second Ads

A study by TVision of viewer attention across Connected TV commercial ad lengths found that approximately a third of viewers paid attention to various ad lengths (15, 30 and 60 second), which suggests that advertisers have the opportunity to engage CTV viewers, no matter the ad length. 

However, the similarities end there. The same study revealed that 15-second ads outperformed other ad lengths across all types of Connected TV apps, when measuring the percentage of the total ad that captured attention at 48%:

  • 30-second ads: Average 36%
  • 60-second ads: Average 19%

Short-Form Ads Prompt Recall and Choice

Shorter ads not only drive more site visits, they are more efficient overall across recall and choice, otherwise known as ‘attentionally efficient.’ A study by WARC revealed that a few seconds of a short-form TV ad had a bigger attention impact than someone who viewed the same duration of a longer commercial. 

Additionally, this same study found that paying attention to four seconds of one ad on one platform could have a very different impact to four seconds on a different kind of screen. 

For example, comparing short-form ads on digital versus television reveals two stark differences:

  • Viewable time and forced viewing drive the most attention on digital
  • Visibility and program type drive the most attention on television

More is Less: Second Exposures Aid Brand Storytelling

Short-form TV ads (between five to seven seconds) scored roughly the same across ad memorability and brand affinity than their longer-form counterparts (15- and 30-second), however research revealed that they tend to deliver despite the shorter ad-length:

  • Six-second ads delivered 60% of the impact of a traditional 30-second ad
  • 15-second ad spots yielded 80% of the effectiveness of a 30-second ad. 

This doesn’t mean that advertisers should automatically switch their strategy to shorter ad formats like six second ads, since these types of ads generally do not allow time for emotional storytelling. In fact, a study by the Advertising Research Foundation found that these types of ads perform best when served as ‘reminders’, following 30- or 60-second ads, or running alongside longer ads or supporting wider campaigns. Advertisers who diversify their efforts across channels like Connected TV and social, for example, can use one channel to enhance the other’s impact.

The same study by MediaScience and Ehrenberg-Bass tested this hypothesis, testing a longer-form ad of 30 seconds followed up with shorter-form ads lasting seven or 15-seconds. There was no difference between these two experiences, which means “…the seven [second ad] can be used as a ‘kicker’ in the same kind of level that you would use a 15,” said Duane Varan, CEO of MediaScience. The research team then looked at the response to a seven-second ad run alone, followed by a second ‘exposure’ of the same length, or of a 30-second ad spot. Here it was found that the seven-second ad spot benefited from having the 30-second ad run after it. “Having the full story, then being reminded of it [with the short-form ad] improved ad likeability for the seven,” concluded Varan.


The power of short-term video is clear—research revealed that attention did not change much depending on 15, 30- and 60- advertisements, but advertisers need to go beyond ad-length, such as divert their efforts to the type of content they are serving their ads and diversifying efforts on television—including adding a ‘second exposure’ to their advertising campaigns.

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