HBO Max is getting into thumbnail testing — 9 years after Netflix

Business Insider

18-07-2025

HBO Max plans to start testing different photo thumbnails for movies like "Sinners," starring Michael B. Jordan.
HBO Max plans to start testing different photo thumbnails for movies like "Sinners," starring Michael B. Jordan. Warner Bros.
HBO Max plans to start testing different photo thumbnails for movies like "Sinners," starring Michael B. Jordan. Warner Bros.
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Better late than never.
Warner Bros. Discovery is preparing to roll out A/B testing on HBO Max photo thumbnails for the first time, two employees familiar with the project told Business Insider. A company spokesperson confirmed the effort.
The project, which one employee nicknamed the "multi-armed bandit," will randomly display one of several different thumbnails — the small preview images you see for a TV show or movie before you click — for each HBO Max title. After the tests, the system will show all users the thumbnail that drives the most engagement.
The rollout shows how WBD's flagship streamer is playing catch-up to rivals like Netflix, which publicly confirmed it was A/B thumbnail testing nine years ago, in May 2016.
Disney+, Hulu, and Peacock also started A/B thumbnail tests years ago. And Paramount+ started A/B testing images last year, which the company said boosted its click-through rate by 162%.
WBD has previously used A/B tests in other ways but hasn't applied them to thumbnails.
HBO Max will first test thumbnails on a small number of popular TV shows and movies, and if all goes well, plans to roll out the program across most of the streamer's catalog in the first half of 2026, an employee close to the project said.
This person added that WBD eventually wants to personalize thumbnails by tailoring them to specific users, like Netflix does.
Beyond the paid streamers, thumbnails have become something of an obsession for social-media creators.
Top YouTuber MrBeast has a team dedicated to making thumbnails that generated about 50 iterations per video as of last year, according to Chucky Appleby, who oversaw the effort at the time.
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The future is AI
HBO Max's thumbnail variations will initially be created by humans, the employee close to the project said. However, they eventually expect that to change.
"AI isn't incorporated now, but that is the plan," this person said.
The spokesperson confirmed AI would help scale thumbnail selection eventually, though humans would remain involved.
Streamers are racing to add AI to their platforms. Netflix has debuted an AI search tool and also recently refreshed its layout to include vertical video. Some analysts say it should go a step further by adding more short-form content to better compete with YouTube and TikTok.
As for WBD's AI efforts in streaming, HBO Max uses AI to improve content recommendations. It revamped its personalization system last summer. The company said these changes meaningfully improved viewership time, return visits, homepage-to-playback conversions, and titles watched.
Three WBD software engineers told BI that HBO Max's tech has room for improvement, but has come a long way.
"It's not that smart, but the recommendation system does its job," a WBD software engineer told BI.