Grok 3 and ChatGPT showdown: Is Musk’s new AI really the best LLM on Earth?

The short answer? Probably not. Things are ramping up quick in the AI world, which means we need to look beyond just Grok 3 and ChatGPT to see the full picture.

When Elon Musk launched Grok 3 in beta, he declared it king, hinting “this might be the last time that any AI is better than Grok”.

But just one week after Grok 3’s release, Anthropic woke up from its long nap and unleashed Claude 3.7 Sonnet, now celebrated as the top AI for coding.

What we’re really seeing is that no AI is untouchable anymore. The AI “space race” is ramping up with contender after contender. Each one is the best at something—until it’s not. 

So what exactly is Grok 3, and why should SEOs and marketers care?

Grok 3 origins: Another AI titan emerges

Elon Musk’s new AI giant is his self-purportedly “scary smart” answer to the AI arms race. 

Grok 3 is xAI’s successor to Grok 2, launched in beta by Musk in mid February 2025. It has roughly 15x more compute and a “thinking” mode to rival top-tier reasoning models like ChatGPT’s o3-mini, Claude’s 3.7 Sonnet, and DeepSeek’s R1. Grok 3 earned an impressive ELO score of 1400 in blind tests, flexing its capabilities in self-critique, solution verification, backtracking, and first-principles reasoning.

The name “Grok” comes from a Robert Heinlein novel “Stranger in a Strange Land”. It means to deeply and profoundly understand something—a nod to xAI’s mission to understand the universe through truth-seeking AI.

For SEOs, Grok-3’s benchmark performance and reasoning capabilities make it a handy AI tool for some SEO tasks.

We’ll pit it against top contenders like ChatGPT, Claude, and DeepSeek to see if it lives up to Musk’s claim of being “scary smart” and if it’s worth your time.

Grok 3 vs ChatGPT and other AI Models

Please note: Accurately determining AI supremacy is tricky, especially when benchmarks are set by the team behind the AI itself, so keep that in mind. Claims of being the best are often based on cherry-picked or manipulated results, and Musk’s team created the benchmarks shown below.

To showcase Grok 3’s strengths, Musk hosted a Chatbot Arena (LMSYS) showdown, pitting an early version of xAI’s top model—codenamed Chocolate—against other leading LLMs in thousands of blind tests. Its ELO score—a dynamic chess rating system now applied to AI—reached about 1400, blowing past every other contender.

Musk’s team refined Grok 3 by selecting its best pre-trained version and boosting it with reinforcement learning. This upped its reasoning capabilities and drove its high scores in blind tests.

Grok 3 also outperformed competing models in reasoning and test-time computing. This took it to the top for math, science, and coding. Check the infographic below to see Grok leapfrogging major contenders like o3-mini and DeepSeek R1:

While this graph suggests that xAI has obliterated OpenAI in areas like multi-step math problem-solving and writing mid-level code, it’s misleading. 

Musk conveniently left out OpenAI’s flagship reasoning model (base o3) since its benchmarks are still half-hidden. That’s a little too easy, so let’s dig into what we do know about OpenAI’s base o3 model for a more faithful comparison between xAI and OpenAI.

Grok 3 versus ChatGPT-o3

OpenAI’s o3 is most likely the top contender despite xAI’s claims of benchmark supremacy. The edited graph below shows OpenAI’s o3 model outperforming Grok 3’s reasoning skills in math and science.

This graph doesn’t show o3’s 71.7% score for coding and software engineering, but Musk’s team ran Grok 3 through a different benchmark (LCB) than OpenAI’s choice for o3 (SWE-Bench Verified). So Grok 3’s impressive 75% and 80% scores might not hold water under the same testing conditions as o3.

Disclaimer: OpenAI has only tested the complete version of o3 in experiments. It isn’t available for commercial use, except in a limited version called Deep Research. The full Deep Research version is offered exclusively to OpenAI Pro users.

OpenAI’s simulated reasoning versus Grok 3’s “Think” mode

OpenAI’s o3 uses simulated reasoning, while Grok 3 uses a simpler version dubbed ‘Think mode’. Their approaches differ in scope:

• Speed versus comprehension: OpenAI’s base o3 model uses its full reasoning capacity, but its output is slower than Grok 3’s quicker, smooth responses.
• Reasoning effort adjustment: OpenAI’s o3-mini variants let you choose from low, medium, or high reasoning effort. A Grok 3-mini variant exists, but only Grok 3 beta is currently available, and you can’t adjust its reasoning effort yet.

For digital marketers, o3 is the better option for producing meatier content. It uses its full simulated reasoning to generate detailed, well-organized, and in-depth responses. You’ll have more luck creating authoritative, contextually rich, human-like copy with it.

Meanwhile, Grok 3’s “Think mode” pushes for speed and produces punchy, ad-friendly text. It’s the better option for rapid-fire content updates or catchy headlines.

Research depth

The speed versus depth trend continues.

OpenAI’s full Deep Research feature has an incredibly high research output. Powered by the base o3 model, it can think for up to 30 minutes and give responses as long as 100,000-tokens—roughly 75,000 words. It also has a 200,000 token context window. 

Grok 3 hasn’t shared details on its context window or max output tokens yet, but it has a similarly named feature, DeepSearch, that operates on a much smaller scale. Musk’s AI caps its thinking time at a few minutes, but it produces quick responses between 1000 and 2000 words.

OpenAI’s Deep Research is the winner for in-depth competitor or keyword research. The catch? There’s no way to access o3’s reports before shelling out $200 a month.

Cost-effectiveness: Adding o3-mini into the mix

If you’re on a budget and don’t need to write a thesis paper for your clients, Grok 3 is easier on the wallet. It’s also faster. But OpenAI’s o3-mini variants match up well with Grok 3 and come in $10 cheaper.

• Deep Research (aka ChatGPT-o3): $200/month Pro plan gives you max access (120 uses) to its Deep Research feature and 200K context window. 
• o3-mini: $20/month Plus plan unlocks OpenAI’s o3-mini variants. You only get 10 Deep Research requests and a smaller context window, but its capabilities rival Grok’s DeepSearch in depth and range.
• Grok 3: Its DeepSearch feature is accessible by upgrading to SuperGrok on Grok.com ($30/month) or purchasing an X Premium + subscription ($40/month)

The o3-mini variants rival Grok 3 because they let you adjust the reasoning effort—low, medium, or high—to fine-tune the trade-off between speed and analytical depth. 

Grok 3’s DeepSearch and “Think mode” features are fixed and favor low analytical depth, but with no usage caps. 

For SEOs with room in their budget who value flexible reasoning and rich insights for detailed reports, OpenAI’s Deep Research (base o3) and its mini variants (limited Deep Research) edge out Grok 3. But Musk’s AI still has its place. Grok 3’s comparatively surface-level research feature has unlimited uses and is ideal for rapid, ad-friendly outputs.

Grok 3 versus everyone

Musk’s claim that Grok 3 is “the best AI on Earth” is untrue, but its benchmarks hold out. Musk’s AI’s capabilities stand up well against competitors like Claude 3.7 Sonnet, ChatGPT-o3, ChatGPT-o3-mini, and DeepSeek R1. This is great news for SEOs—it means more choices and competitive API token prices.

The table below shows how Grok 3 stacks up commercially against other leading AI models.

SEOs should see this chart as proof that Grok 3 is more than just another AI model entering the market. Its emergence—mirroring DeepSeek’s—is driving broader industry trends. 

With its competitive “Think” mode, nifty “DeepSearch” feature, and affordable pricing, Grok 3 shows that AI is becoming more dynamic and cost-effective. 

But where does Grok 3 stand on a practical level? Let’s move beyond the theoretical and see how Grok 3 performs on SEO tasks compared to its rivals.

Real-World SEO Face-Off: Grok 3 Against other AI Titans

LLMs are getting pretty good at doing some SEO work, but not all. Hypercomplex SEO tasks like website auditing, keyword research, and backlink monitoring are best left to designated tools like SE Ranking.

But you can get Grok 3 and its rivals to work magic with content creation, topical research, and AI-detection dodging. 

Content Creation

We asked Grok 3 (beta), o3 mini, Claude 3.7 Sonnet, and DeepSeek R1 to create an enjoyable SEO-optimized article for the keyword, deepseek ai seo. The prompt was simple; we didn’t give further instructions or use added features like o3-mini’s Deep Research or Grok 3’s “Think” mode.

Here’s how each model performed:

Claude 3.7 Sonnet was the clear winner in this test. It was the only model that knew—without having to tell it—that deepseek ai seo is not a natural phrase. Claude found creative ways to work around this awkward keyword and wrote headings that made sense. 

But all AI models had cliche introductions, each saying something like “In today’s digital landscape, staying ahead of search engine algorithms is crucial for online visibility.” 

Not a single AI deviated from this narrative.

Topical research

Popular SEO YouTuber Julian Goldie also performed some experiments. After testing o3-mini, Grok 3, and Perplexity’s advanced research features, he noticed differences in each model’s depth and breadth.

Here’s how the three AI and their research features stacked up when asked to find the most up-to-date information on Grok 3:

According to Goldie, o3-mini and its Deep Research feature was the clear winner for its thorough and unbiased research—great for YMYL topics—but he gave a nod to Perplexity and its impressive output given that it’s free to use. 

Goldie said that Grok 3 was decent but its quick, to-the-point reports were unsuitable for the dense topical research needed for SEO content.

AI-detectability

Goldie asked o3-mini, DeepSeek R1, and Grok 3 to create an article that was 100% non-AI-detectable. He tested them with the online tool, ZeroGPT. Here’s what he found:

• o3-mini: Easy to detect, at 78% AI
• Grok (normal mode): Still pretty easy to detect, at 62%
• Grok 3 (think mode): Much worse than expected, at 95% AI
• DeepSeek: Clearly AI, at 100% detectability

We tested Claude 3.7 Sonnet with the same prompt. It created a surprisingly human-like article about digital minimalism, titled “The lost art of being untouchable.” It got a 24% AI-detectability score, with ZeroGPT suspecting that “some sentences or passages may have been edited by AI.”

AI Showdown Summary Chart: A detailed snapshot

Check out the chart below for a closer look at how Grok 3 stacks up against competing AI titans. It distills our findings into a single snapshot, highlighting which AI excels where for SEO.

This face-off showed that Claude 3.7—not Grok 3—gives the most standout responses. It created the most natural, human-like content and rarely triggered AI detectors. 

But we also noticed that each model performs differently under different conditions. Since testing is speculative, we suggest experimenting with each AI yourself to find the best fit.

What Grok 3 means for the future of AI

Musk’s AI accelerated an already rapid pace of AI advancement. 

The proof? 

Major model releases and updates used to occur every few months, but the pace has quickened. 

When we started writing this article, Grok 3 just launched. One week later, it unleashed a controversial voice mode feature that can argue with users and even swear at them. Then Claude 3.7 Sonnet arrived in late February 2025 with its groundbreaking hybrid reasoning approach, and OpenAI released GPT‑4.5 to Pro and Plus users just days after that, with improved emotional intelligence and far fewer hallucinations.

Grok 3’s launch is Elon Musk’s move to claim a piece of the AI market while it’s booming. 

And while no single AI model currently excels at everything, each is finding its niche. We expect that trend to continue:

The days of “one AI to rule them all” are behind us. And whether Elon Musk’s claim about Grok 3 being the “best AI on Earth” proves true or not is less important than his role in pushing the snowball further down the hill to democratize the AI market. 

For digital marketers and SEOs, that’s a win because we get better tools, and more of them—and more competition means friendlier prices.

Victor is the meticulous copy editor behind SE Ranking’s polished content. By day, he proofreads and localizes SE Ranking’s English-language content, sharpens marketing copy, and updates the company’s style and formatting guide. He is also a prolific writer with a background in journalism and a passion for SEO. He’s an AI enthusiast, scouring tech news daily to learn more about the field and its growing impact on search. Off the clock, you might find him curled up in a cozy library nook with a book and a Hydro Flask of coffee within reach.