Grok 4 vs ChatGPT 5 performance, features, and accuracy in 2025 benchmarks

Grok 4 vs ChatGPT 5 is one of the most discussed comparisons in the AI market.

Both models were released in mid-2025, targeting different strengths. Grok 4, developed by xAI, launched on July 9, 2025, with a focus on tool use, coding precision, and real-time search. ChatGPT 5, launched by OpenAI on August 7, 2025, offers improved reasoning, writing, and general knowledge performance, while reducing hallucination rates compared to its predecessors.

Independent benchmarks show ChatGPT 5 leading in general reasoning and knowledge tests. In MMLU, a major benchmark for general knowledge, ChatGPT 5 scored 86.4%, outperforming Grok 4. On LiveBench, ChatGPT 5 maintained high accuracy in logical reasoning and structured responses. Grok 4, however, scored higher in technical tests such as HumanEval for coding, where it reached 75%, compared to ChatGPT 5’s 67%. On AIME 2025, a mathematics benchmark, Grok 4 reached 95%, showing its advantage in structured problem-solving.

Accuracy gap grows between models

Hallucination rates reveal a significant gap. ChatGPT 5 has an average hallucination rate of 1.4%, lower than GPT-4’s 1.49%. Grok 4’s hallucination rate remains higher at 4.8%, which impacts trust in long-form knowledge responses. This aligns with feedback from developers who report that Grok’s answers are faster but sometimes omit citations or detailed explanations.

Grok 4 includes features like real-time search, a programming-specialized Grok 4 Code version, and integration into Tesla vehicles for in-car AI access. It also supports “Companions” mode with interactive avatars. ChatGPT 5 focuses on improving conversational safety and factual accuracy, adding Safe Completions to reduce unsafe content without excessive filtering. It also has a refined tone system to provide critical feedback rather than being overly agreeable.

Grok 4 is available through Premium+ and SuperGrok subscriptions, with temporary free access introduced in August 2025. The free tier allows limited queries per 12-hour period, making it suitable for occasional users. ChatGPT 5 is available across all tiers, including free access, but Plus and Pro subscribers get higher usage limits and priority speed. Developers benefit from API access to both models, though Grok’s API availability remains more restricted.

Safety concerns remain in focus

Both platforms face safety challenges. Grok 4 has drawn criticism over its “Spicy” and NSFW modes, which have raised concerns about potential misuse for deepfake content. Some consumer safety groups have urged regulatory bodies to investigate. ChatGPT 5 has undergone security audits to identify vulnerabilities, with one report showing that it could be manipulated into producing harmful instructions. Both companies have increased moderation, but trade-offs between safety and model flexibility remain.

For developers, Grok 4’s speed and coding accuracy make it appealing for rapid prototyping and debugging. Its tool integration and real-time search provide value for technical workflows. ChatGPT 5 offers broader utility in academic research, content creation, and customer support due to its lower hallucination rate and more balanced output style. Users seeking safe, fact-checked responses may prefer ChatGPT 5, while those who need fast, code-heavy solutions may lean toward Grok 4.

Choosing the right model for your goals

Selecting between Grok 4 and ChatGPT 5 depends on your priorities. If your work demands minimal factual errors and clear explanations, ChatGPT 5 is the stronger choice. If technical problem-solving and fast iteration are key, Grok 4 delivers more in specific benchmarks.

Here’s a clear and up‑to‑date comparison between Grok 4 and ChatGPT‑5, based on the latest sources:

Overview & Launches

Grok 4 (xAI): Released on July 9, 2025, by Elon Musk’s xAI. It’s positioned as the company’s most advanced model, featuring native tool integration and real‑time search. A more powerful variant, Grok 4 Heavy, is also available.

ChatGPT‑5 (OpenAI): Launched on August 7, 2025, as the new flagship GPT model. Available across ChatGPT tiers and API access.

Performance & Benchmarks

ChatGPT‑5 leads many benchmark tests for reasoning, mathematics, coding, and visual understanding across platforms like Vellum, Artificial Analysis, LMArena, and LiveBench. However, it placed fifth, behind Gemini and Claude, on the SimpleBench social intelligence test.

ChatGPT‑5 also shows a lower hallucination rate (1.4%) compared to GPT‑4 (1.8%) and GPT‑4o (1.49%). Grok 4, by contrast, still has a significantly higher hallucination rate at 4.8%.

Another comparison highlights:

Grok 4 excels in technical benchmarks, especially coding on HumanEval (72–75% vs ChatGPT‑5’s 67%), AIME 2025 (95%), and GPQA (87.5%).
ChatGPT‑5 edges ahead on general knowledge via MMLU (86.4%).

Reviews note that ChatGPT‑5 sometimes prioritizes speed at the expense of thoroughness. Grok 4 responds swiftly but may omit citations.

Features & Capabilities

Grok 4 offers:

• Real‑time search integration and native tool use.
• A programming‑specialized variant called Grok 4 Code.
• “Think” reasoning modes from earlier versions.
• Integration into Tesla vehicles (chat-only, no control over vehicle functions).
• A “Companions” feature with animated characters, including NSFW‑capable avatars.

ChatGPT‑5 enhancements include:

• Faster responses, improved coding and writing skills, more accurate health answers, and reduced hallucinations.
• A “Safe Completions” feature aiming to provide safer responses while minimizing unnecessary rejections.
• A more critical tone trained to avoid excessively agreeable answers.

Access & Availability

Grok 4: Initially rolled out to Premium+ and SuperGrok subscribers; a free tier became available temporarily in mid‑August 2025, but with a daily or time‑based query limit (e.g., five queries per 12 hours).

ChatGPT‑5: Accessible to all users (Free, Plus, and Pro), with higher usage limits for paid tiers.

Controversies & Safety

Grok 4 has drawn criticism for:

• Its “Spicy” and NSFW modes—risk of deepfake misuse and non‑consensual content, prompting consumer safety groups to call for regulatory investigation.
• Debatable moderation and age verification measures.
• Past extremist outputs (e.g. antisemitic content), prompting internal changes that impacted its behavior.

ChatGPT‑5: Security audits suggest possible exploitation around sensitive topics—for example, one firm was able to make it generate instructions for explosive devices.

Summary Table

Verdict

• Choose Grok 4 if your focus is high-precision technical or coding tasks and you value speed and tool integration.
• Choose ChatGPT-5 if you need broad general knowledge, creative writing, accuracy, and a safer, more polished user experience.