McDonald’s v Burger King: who wins the AI burger battle?

With typical agility, rivals Burger King quickly became the second brand to turn ChatGPT output into an ad, running a billboard ad right next to it with the follow-up prompt ‘And which is the biggest?’ – the Whopper. Apparently.

It’s all good fun, and the executions perfectly summarize both brands’ positioning and tactics – McDonald’s the category boss, Burger King the cheeky challenger pointing out that just maybe it offers more.

But is a ChatGPT endorsement really good for the brand? Is it even credible? The great thing with ChatGPT is that you can try the prompts yourself at home. I did, and while ChatGPT does identify the Big Mac as an iconic burger, for me it was just one of a list. As for the biggest burgers, the Whopper didn’t feature in my answers.

This isn’t a knock on McDonald’s or Burger King - anyone who’s worked with generative AI knows creative prompting and output editing are critical skills. But it’s a reminder that AI outputs aren’t a scientific survey. They’re more like that one person in a focus group who happens to say exactly what you wanted after two hours and a few glasses of free wine.

Would audiences care about ChatGPT’s verdict?

Which ad was more effective?

To answer this we ran both through our Test Your Ad platform, which predicts the long- and short-term business impact of ads. We also used the Test Your Ad Digital to rate the digital video execution McDonald’s created to accompany the ad.

The results? Ironically for the two great rivals, it’s a draw.

Both billboard ads scored 2.9 stars on Test Your Ad. Perhaps this shouldn’t surprise anyone - it’s the same idea and execution, after all.

For an out-of-home ad, that’s not a bad score – it’s slightly above the 2.4-star UK average. But copywriters needn’t panic – it’s hardly a world-beating performance from the robots. At least not this time. While generative AI is improving all the time, none of the “pure” AI ads we’ve tested – text or video – have really moved the needle emotionally. For four- or five-star ads, the human touch is very much required.

In fact, the AI involvement barely registered with viewers of the billboard ads. AI copy is already invisible to the average reader, even when it’s the whole point of the ad. People read the ads as very straightforward product claims and their opinion of them was mostly their opinion of the brand. AI and ChatGPT figured nowhere in the “key associations” for either ad, and the few comments weren’t always flattering. “Jumping on the ChatGPT bandwagon YAWN,” wrote one participant – showing it’s not just marketers who are rolling their eyes at some of the hype.

As marketers, we’ll always love a topical idea and a snappy response. But what gets us worked up doesn’t always register with the public. Brand managers don’t need to scramble for a ChatGPT endorsement.

The fact that barely any ordinary viewers noticed AI involvement in this work might be a sign we’re finally ready for the next phase of AI ads, where it stops being a gimmick, and starts just being a tool. The new threat of AI job replacement isn’t as risky for your career as the much older menace of marketers impressing each other, not the people they’re selling to.

Oh and if you are wondering what the best podcast in the world is according to ChatGPT it’s Uncensored CMO. Just don’t ask me to prove it.

Update: Shortly before this piece was published Subway also jumped in on the craze.

Evans also heads up the UK’s most-liked ads each month.