Model Comparison
Gemini 2.5 Pro vs Grok-4 HeavyWhich is better in 2026?
Grok-4 Heavy significantly outperforms across most benchmarks.
Verdict: Gemini 2.5 Pro vs Grok-4 Heavy — which is better?
Gemini 2.5 Pro (by Google) and Grok-4 Heavy (by xAI) are two of the AI models people compare most. Here is how they stack up on benchmarks, price and capabilities, and which one to pick in 2026.
Gemini 2.5 Pro outperforms in 0 benchmarks, while Grok-4 Heavy is better at 3 benchmarks (AIME 2025, GPQA, Humanity's Last Exam). Grok-4 Heavy significantly outperforms across most benchmarks.
Choose Gemini 2.5 Pro if…
- you want predictable pricing at $1.25/M input and $10.00/M output
Choose Grok-4 Heavy if…
- you want the strongest raw capability — it leads on 3 of 3 shared benchmarks
Performance Benchmarks
Comparative analysis across standard metrics
Gemini 2.5 Pro outperforms in 0 benchmarks, while Grok-4 Heavy is better at 3 benchmarks (AIME 2025, GPQA, Humanity's Last Exam).
Grok-4 Heavy significantly outperforms across most benchmarks.
Arena Performance
Human preference votes
Context Window
Maximum input and output token capacity
Only Gemini 2.5 Pro specifies input context (1,048,576 tokens). Only Gemini 2.5 Pro specifies output context (65,536 tokens).
Input Capabilities
Supported data types and modalities
Both Gemini 2.5 Pro and Grok-4 Heavy support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Gemini 2.5 Pro
Grok-4 Heavy
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
Gemini 2.5 Pro was released on 2025-05-20, while Grok-4 Heavy's release date is not specified.
We can confirm Gemini 2.5 Pro's release timeline, but cannot make a direct age comparison without Grok-4 Heavy's release date.
May 20, 2025
1.1 years ago
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Knowledge Cutoff
When training data ends
Gemini 2.5 Pro has a knowledge cutoff of 2025-01-31, while Grok-4 Heavy has a cutoff of 2024-12-31.
Gemini 2.5 Pro has more recent training data (up to 2025-01-31), making it potentially better informed about events through that date compared to Grok-4 Heavy (2024-12-31).
Jan 2025
1 mo newerDec 2024
Outputs Comparison
Key Takeaways
Gemini 2.5 ProGrok-4 HeavyDetailed Comparison
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FAQ
Common questions about Gemini 2.5 Pro vs Grok-4 Heavy.