Every month, hundreds of millions of users flock to Pinterest looking for the latest styles.

One page titled “the most ridiculous things” is filled with plenty of wacky ideas to inspire creatives. Crocs repurposed as flower pots. Cheeseburger-shaped eyeshadow. A gingerbread house made of vegetables.

But what would-be buyers may not know is the tech behind this isn’t necessarily US-made. Pinterest is experimenting with Chinese AI models to hone its recommendation engine.

“We’ve effectively made Pinterest an AI-powered shopping assistant,” the firm’s boss Bill Ready told me.

Of course, the San Francisco-based tastemaker could use any number of American AI labs to power things behind-the-scenes.

But since the launch of China’s DeepSeek R-1 model in January 2025, Chinese AI tech has increasingly been a part of Pinterest.

Ready calls the so-called “DeepSeek moment” a breakthrough.

“They chose to open source it, and that sparked a wave of open source models,” he said.

Chinese competitors include Alibaba’s Qwen and Moonshot’s Kimi, while TikTok owner ByteDance is also working on similar technology.

Pinterest Chief Technology Officer Matt Madrigal said the strength of these models is that they can be freely downloaded and customised by companies like his – which is not the case with the majority of models offered by US rivals like OpenAI, which makes ChatGPT.

“Open source techniques that we use to train our own in-house models are 30% more accurate than the leading off-the-shelf models,” Madrigal said.

And those improved recommendations come at a much lower cost, he said, sometimes ninety percent less than using the proprietary models favoured by US AI developers.

Pinterest is hardly the only US enterprise depending on AI tech from China.

These models are gaining traction across an array of Fortune 500 companies.

Airbnb boss Brian Chesky told Bloomberg in October his company relied “a lot” on Alibaba’s Qwen to power its AI customer service agent.

He gave three simple reasons – it’s “very good”, “fast” and “cheap”.

Further evidence can be found on Hugging Face, the place people go to download ready-made AI models – including from major developers Meta and Alibaba.

Jeff Boudier, who builds products at the platform, said it is the cost factor that leads young start-ups to look at Chinese models over their US counterparts.

“If you look at the top trending models on Hugging Face – the ones that are most downloaded and liked by the community – typically, Chinese models from Chinese labs occupy many of the top 10 spots,” he told me.

“There are weeks where four out of five top training models on Hugging Face are from Chinese labs.”

In September, Qwen topped Meta’s Llama to become the most downloaded family of large language models on the Hugging Face platform.

Meta released its open-source Llama AI models in 2023. Up until the release of DeepSeek and Alibaba’s models, they were considered the go-to choice for developers working on bespoke applications.

But the release of Llama 4 last year left developers underwhelmed, and Meta has reportedly been using open-source models with Alibaba, Google, and OpenAI to train a new model set for release this spring.

Airbnb also uses several models, including US-based ones, hosting them securely in the company’s own infrastructure. The data is never provided to the developers of the AI models they use, according to the company.

Going into 2025, the consensus was despite billions of dollars being spent by US tech firms, Chinese companies were threatening to pull ahead.

“That’s not the story anymore,” Boudier said. “Now, the best model is an open-source model.”

A report published last month by Stanford University found Chinese AI models “seem to have caught up or even pulled ahead” of their global counterparts – both in terms of what they’re capable of, and how many people are using them.

In a recent interview with the BBC, former UK deputy prime minister Sir Nick Clegg said he felt US firms were overly focused on the pursuit of AI which may one day surpass human intelligence.

Last year, Sir Nick left his post as head of global affairs at Meta, the developer of Llama. Boss Mark Zuckerberg has committed billions of dollars to achieving what he calls “superintelligence.”

Some experts are now calling these ambitions vague and ill-defined – giving China an opening to dominate the open-source AI space.

“Here’s the irony,” Sir Nick said. In the battle between “the world’s great autocracy” and “the world’s greatest democracy” – China and America – China is “doing more to democratise the technology they’re competing over”.

The Stanford report also suggested China’s success in developing open-source models could be partly explained by government support.

On the other side of the world, US companies like OpenAI are under intense pressure to increase revenue and become profitable – and is now turning to ads to help get there.

The company released two open-source models last summer – its first in years. But it has poured most of its resources into proprietary models to help it make money.

OpenAI boss Sam Altman told me in October it has invested aggressively into securing ever more computing power and infrastructure deals with partners.

“Revenue will grow super fast, but you should expect us to invest a ton in training, in the next model and the next and the next and the next,” he said.