Gemini 3.1 Pro vs Grok 3
Gemini 3.1 Pro vs Grok 3: Gemini 3.1 Pro is cheaper for input-heavy usage ($2.00/M vs $3.00/M input tokens), while Gemini 3.1 Pro is better for long-context tasks (1,000,000 tokens).
Direct answer: choose Gemini 3.1 Pro for lower token spend and choose Gemini 3.1 Pro when your workload needs longer context.
Compare input and output token pricing, context windows, and monthly cost estimates on one page so you can pick the cheaper model fast.
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
Gemini 3.1 Pro
Grok 3
Cost Differences
Grok 3 costs more than Gemini 3.1 Pro
Quick Recommendation
Winner for direct API pricing: Gemini 3.1 Pro. At the default workload, Gemini 3.1 Pro saves about $7.50/month ($91.25/year) versus Grok 3.
Feature Comparison
| Feature | Gemini 3.1 Pro | Grok 3 |
|---|---|---|
| Provider | xAI | |
| Input Price | $2.00/1M tokens | $3.00/1M tokens |
| Output Price | $12.00/1M tokens | $15.00/1M tokens |
| Context Window | 1,000,000 tokens | 131,072 tokens |
| Max Output | 65,536 tokens | 131,072 tokens |
| Category | flagship | flagship |
| Capabilities | textvisionaudiovideocodereasoning | textvisionreasoningcode |
| Release Date | 2/19/2026 | 2/17/2025 |
Gemini 3.1 Pro vs Grok 3: Which Should You Choose?
Choosing between Gemini 3.1 Pro and Grok 3 depends on your priorities: cost efficiency, context length, or raw capability. Gemini 3.1 Pro is the more affordable option at $2.00/1M input tokens — 33% cheaper than Grok 3. Meanwhile, Gemini 3.1 Pro offers a significantly larger context window at 1,000,000 tokens vs 131,072 for Grok 3.
These models come from different providers — Google and xAI — which means different API ecosystems, SDKs, rate limits, and terms of service. If you're already integrated with Google, switching to xAIinvolves migration effort beyond just pricing. Factor in your existing infrastructure when deciding.
Both models are in the flagship category, making this a direct head-to-head comparison. At scale — say 10,000 requests per day — the cost difference adds up: Gemini 3.1 Pro would save you roughly $750.00/month compared to Grok 3. For startups and indie developers, that difference can be significant.
Output costs matter too. Gemini 3.1 Pro charges $12.00/1M output tokens vs $15.00 for Grok 3. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. Gemini 3.1 Pro has the edge here at $12.00/1M output tokens.
Multimodal capabilities: Both models support vision (image understanding), so you can send images alongside text prompts with either option.
Best Use Cases
Choose Gemini 3.1 Pro when:
- • Budget is a primary concern
- • You need a larger context window (1,000,000 tokens)
- • You need more capabilities (audio, video)
- • You're already using Google's API ecosystem
Choose Grok 3 when:
- • You need longer outputs (up to 131,072 tokens)
- • You're already using xAI's API ecosystem
Pros and Caveats at a Glance
Gemini 3.1 Pro
- • Input pricing: $2.00/M tokens
- • Output pricing: $12.00/M tokens
- • Context window: 1,000,000 tokens
- • Max output: 65,536 tokens
Watch out for
- • Trade-offs are minor in this matchup.
Grok 3
- • Input pricing: $3.00/M tokens
- • Output pricing: $15.00/M tokens
- • Context window: 131,072 tokens
- • Max output: 131,072 tokens
Watch out for
- • Higher input cost than Gemini 3.1 Pro
- • Higher output cost than Gemini 3.1 Pro
- • Smaller context window than Gemini 3.1 Pro
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
Gemini 3.1 Pro (Google)
Grok 3 (xAI)
Start using Gemini 3.1 Pro today
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Sign Up for xAI →Frequently Asked Questions
Which is cheaper, Gemini 3.1 Pro or Grok 3?▼
What is the context window difference between Gemini 3.1 Pro and Grok 3?▼
Which model is better for AI Agent / Agentic Workflows?▼
Which model has better overall pricing for heavy usage?▼
Where can I compare Google and xAI API pricing beyond this model matchup?▼
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