Gemini 2.5 Pro vs GPT-5.1
Pricing verdict: Gemini 2.5 Pro vs GPT-5.1: pricing is a tie at $1.25/M input and $10.00/M output. The real choice is context: Gemini 2.5 Pro is better for long-context tasks (2,000,000 tokens vs 1,000,000).
Direct answer: pricing is a tie. Choose Gemini 2.5 Pro for the larger 2M context window, or pick GPT-5.1 if 1M is already enough for your workload.
Compare API pricing, input and output token costs, context windows, and monthly estimates on one page so you can pick the right model fast.
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
Gemini 2.5 Pro
GPT-5.1
Cost Differences
Both models cost the same at the default workload.
Quick Recommendation
Direct API pricing is a tie at the default workload: both land around $18.75/month. Pick Gemini 2.5 Pro if you need the larger 2M context window; otherwise choose the model that better fits your workflow.
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. Both models cost the same on input and output tokens, so raw price is a tie. 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 — direct API pricing stays tied, so the real decision is context, latency, and provider fit.
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
Pros and Caveats at a Glance
Gemini 2.5 Pro
- • Input pricing: $1.25/M tokens
- • Output pricing: $10.00/M tokens
- • Context window: 2,000,000 tokens
- • Max output: 131,072 tokens
Watch out for
- • Trade-offs are minor in this matchup.
GPT-5.1
- • Input pricing: $1.25/M tokens
- • Output pricing: $10.00/M tokens
- • Context window: 1,000,000 tokens
- • Max output: 131,072 tokens
Watch out for
- • Smaller context window than Gemini 2.5 Pro
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)
Start using Gemini 2.5 Pro today
Sign Up for Google →Start using GPT-5.1 today
Sign Up for OpenAI →Frequently Asked Questions
Which is cheaper, Gemini 2.5 Pro or GPT-5.1?▼
What is the context window difference between Gemini 2.5 Pro and GPT-5.1?▼
Which model is better for AI Chatbot?▼
Which model has better overall pricing for heavy usage?▼
Where can I compare Google and OpenAI API pricing beyond this model matchup?▼
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