The news: Duolingo is adding attention metric guarantees for advertisers, using Adelaide’s attention unit (AU) metric to set a minimum media-quality threshold for its in-app inventory.

The partnership guarantees a level of attention quality, using data like placement signals and eye-tracking data to measure an ad’s likelihood of driving a business outcome rather than relying on traditional metrics like impressions and viewability. Duolingo will also use AU scores to identify high-attention placements and offer attention reporting as a part of campaign delivery.

A March 2026 audit of Duolingo’s online video inventory that used Adelaide AU found that it scored 34% above Adelaide’s benchmark, per a press release.

Zooming in: AU guarantees help Duolingo stand out among the new wave of advertising market entrants—such as Discord and HP—that are competing for budget.

• Instead of asking buyers to trust reach and completion numbers, it’s giving a third-party benchmark tied to a contractual floor.
• This could lower the risk for marketers testing out a newer platform—Duolingo Ads launched in October 2025—at a time when economic uncertainties may push them to prioritize familiar, high-return channels.

If such guarantees perform well for Duolingo, other publishers who are building in-app inventory may pursue similar deals with vendors, making attention function more like a transactable asset.

Recommendations for marketers: Those testing Duolingo’s guarantees should treat lifts in performance as a starting point of evaluation. However, marketers may hesitate to trust a new metric built by a smaller vendor.

• Continue tracking conversion and brand lift led by media quality to confirm results and measure how ads are capturing notice and contributing to business outcomes.
• Compare AU-guaranteed placements against standard buys in the same campaigns.

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