Gemini 2.5 Flash Preview (Sep '25) (Reasoning) vs Grok 4
Comparing 2 AI models · 6 benchmarks · Google, xAI
Composite Indices
Intelligence, Coding, Math
Standard Benchmarks
Academic and industry benchmarks
Benchmark Winners
Gemini 2.5 Flash Preview (Sep '25) (Reasoning)
No clear wins
Grok 4
- GPQA
- MMLU Pro
- HLE
- LiveCodeBench
- MATH 500
- AIME 2025
| Metric | Go Gemini 2.5 Flash Preview (Sep '25) (Reasoning) | xA Grok 4 |
|---|---|---|
| Pricing Per 1M tokens | ||
| Input Cost | $0.30/1M | $3.00/1M |
| Output Cost | $2.50/1M | $15.00/1M |
| Blended Cost 3:1 input/output ratio | $0.85/1M | $6.00/1M |
| Specifications | ||
| Organization Model creator | xAI | |
| Release Date Launch date | Sep 25, 2025 | Jul 10, 2025 |
| Performance & Speed | ||
| Throughput Output speed | 155.2 tok/s | 37.2 tok/s |
| Time to First Token (TTFT) Initial response delay | 8247ms | 9172ms |
| Latency Time to first answer token | 8247ms | 9172ms |
| Composite Indices | ||
| Intelligence Index Overall reasoning capability | 54.4 | 65.3 |
| Coding Index Programming ability | 42.5 | 55.1 |
| Math Index Mathematical reasoning | 78.3 | 92.7 |
| Standard Benchmarks | ||
| GPQA Graduate-level reasoning | 79.3% | 87.7% |
| MMLU Pro Advanced knowledge | 84.2% | 86.6% |
| HLE Hard language evaluation | 12.7% | 23.9% |
| LiveCodeBench Real-world coding tasks | 71.3% | 81.9% |
| MATH 500 Mathematical problems | — | 99.0% |
| AIME 2025 Advanced math competition | 78.3% | 92.7% |
| AIME (Original) Math olympiad problems | — | 94.3% |
| SciCode Scientific code generation | 40.5% | 45.7% |
| LCR Code review capability | 64.3% | 68.0% |
| IFBench Instruction-following | 52.3% | 53.7% |
| TAU-bench v2 Tool use & agentic tasks | 45.6% | 74.9% |
| TerminalBench Hard CLI command generation | 15.6% | 37.6% |
Key Takeaways
Gemini 2.5 Flash Preview (Sep '25) (Reasoning) offers the best value at $0.30/1M, making it ideal for high-volume applications and cost-conscious projects.
Grok 4 leads in reasoning capabilities with a 87.7% GPQA score, excelling at complex analytical tasks and problem-solving.
Grok 4 achieves a 55.1 coding index, making it the top choice for software development and code generation tasks.
All models support context windows of ∞+ tokens, suitable for processing lengthy documents and maintaining extended conversations.
When to Choose Each Model
Gemini 2.5 Flash Preview (Sep '25) (Reasoning)
- Cost-sensitive applications
- High-volume processing
Grok 4
- Complex reasoning tasks
- Research & analysis
- Code generation
- Software development
Try Models for Free
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Cost Calculator
Gemini 2.5 Flash Preview (Sep '25) (Reasoning) Grok 4 Costs are estimates based on API pricing. Actual costs may vary based on caching, batch processing, and volume discounts.
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