Gemini 2.5 Pro vs GPT-5.1
Compare Google and OpenAI AI models
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
Gemini 2.5 Pro
GPT-5.1
Cost Differences
GPT-5.1 costs less than Gemini 2.5 Pro
Feature Comparison
| Feature | Gemini 2.5 Pro | GPT-5.1 |
|---|---|---|
| Provider | OpenAI | |
| Input Price | $1.25/1M tokens | $1.25/1M tokens |
| Output Price | $10.00/1M tokens | $10.00/1M tokens |
| Context Window | 2,000,000 tokens | 1,000,000 tokens |
| Max Output | 131,072 tokens | 131,072 tokens |
| Category | flagship | flagship |
| Capabilities | textvisionaudiovideocode | textvisionaudiocodereasoning |
| Release Date | 3/25/2025 | 11/12/2025 |
Gemini 2.5 Pro vs GPT-5.1: Which Should You Choose?
Choosing between Gemini 2.5 Pro and GPT-5.1 depends on your priorities: cost efficiency, context length, or raw capability. GPT-5.1 is the more affordable option at $1.25/1M input tokens. Meanwhile, Gemini 2.5 Pro offers a significantly larger context window at 2,000,000 tokens vs 1,000,000 for GPT-5.1.
These models come from different providers — Google and OpenAI — which means different API ecosystems, SDKs, rate limits, and terms of service. If you're already integrated with Google, switching to OpenAIinvolves 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: GPT-5.1 would save you roughly $0.00/month compared to Gemini 2.5 Pro. For startups and indie developers, that difference can be significant.
Output costs matter too. Gemini 2.5 Pro charges $10.00/1M output tokens vs $10.00 for GPT-5.1.
Multimodal capabilities: Both models support vision (image understanding), so you can send images alongside text prompts with either option.
Best Use Cases
Choose Gemini 2.5 Pro when:
- • You need a larger context window (2,000,000 tokens)
- • You're already using Google's API ecosystem
Choose GPT-5.1 when:
- • You're already using OpenAI's API ecosystem
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
Gemini 2.5 Pro (Google)
GPT-5.1 (OpenAI)
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