This chart showing ChatGPT vs. Gemini web traffic should have OpenAI worried

• ChatGPT's web traffic has decreased since November, when Google launched Gemini 3.
• Gemini traffic increased by 28% month-over-month in December, while ChatGPT's traffic decreased by 5.6%, per Similarweb.
• ChatGPT still has the lead, but it could demonstrate shifting tides in the AI race.

OpenAI's recent "code red" over Gemini makes a lot of sense when you look at the data.

While the ChatGPT maker continues to dominate the AI race, competitors are gaining ground. In November, Google released Gemini 3 Pro, the first iteration of its Gemini 3 class of models.

Since then, Gemini web traffic has increased while ChatGPT web traffic declined, according to Similarweb data first highlighted by Menlo Ventures partner Deedy Das.

In December, Gemini traffic increased by 28.4% month-over-month, while ChatGPT traffic decreased by 5.6%, the data shows.

The chart's data only tells part of the story, only accounting for site visits to chatgpt.com and gemini.google.com. It does not factor in use of the consumer apps or other integrations, like Google's AI overviews in Google Search.

And while there's no guarantee that one traffic trend is directly because of the other, the data highlights the shifting tides of the AI race.

Web traffic for both ChatGPT and Gemini are up year-over-year, but their estimated site traffic growth rates are staggeringly different. ChatGPT traffic is up 49.5%; Gemini's traffic is up 563.6%, per Similarweb.

ChatGPT still has a healthy lead. In December, ChatGPT attracted 5.5 billion visitors, according to Similarweb. Gemini came in second with 1.7 billion; DeepSeek, Grok, Character.AI, Perplexity, and Claude all trailed behind with fewer than 400 million visitors each.

After its launch, Gemini 3 was lauded as a potentially market-leading model. It was more visual and creative than previous iterations, and was better at coding.

Google has also flexed its primary advantage over OpenAI: the ability to integrate its AI within its highly used search products. Basically everyone uses Google — OpenAI must convince people to turn to ChatGPT instead of the search giant's products.

OpenAI and Google are also competing in the image generation market. Less than a month after Google released its Nano Banana Pro AI image model, OpenAI announced the launch of ChatGPT Images.

Gemini 3 famously triggered a "code red" at OpenAI. In an internal Slack message, CEO Sam Altman reportedly told staff that OpenAI would prioritize ChatGPT while pushing back other product plans.

In December, Altman said on the "Big Technology" podcast that the company would not be in emergency status "that much longer," and that "code red" periods normally last six to eight weeks.

Altman also said that Gemini 3 did not have "the impact we were worried it might."

"But it did — in the same way that DeepSeek did — identify some weaknesses in our product offering strategy, and we're addressing those very quickly," he added.