Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
GPT-5.1
o3-pro
Cost Differences
o3-pro costs more than GPT-5.1
Feature Comparison
| Feature | GPT-5.1 | o3-pro |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Input Price | $1.25/1M tokens | $20.00/1M tokens |
| Output Price | $10.00/1M tokens | $80.00/1M tokens |
| Context Window | 1,000,000 tokens | 1,000,000 tokens |
| Max Output | 131,072 tokens | 131,072 tokens |
| Category | flagship | reasoning |
| Capabilities | textvisionaudiocodereasoning | textreasoningcode |
| Release Date | 11/12/2025 | 6/10/2025 |
GPT-5.1 vs o3-pro: Which Should You Choose?
Choosing between GPT-5.1 and o3-pro 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 — 94% cheaper than o3-pro.
These models target different tiers: GPT-5.1 is a flagship model while o3-pro is reasoning. This means they're optimized for different workloads. GPT-5.1 is built for complex tasks that require deeper reasoning, while o3-pro offers better value for routine operations.
Output costs matter too. GPT-5.1 charges $10.00/1M output tokens vs $80.00 for o3-pro. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. GPT-5.1 has the edge here at $10.00/1M output tokens.
Multimodal capabilities: GPT-5.1 supports vision (image inputs) while o3-pro is text-only. If your application needs image understanding, this narrows your choice.
Best Use Cases
Choose GPT-5.1 when:
- • Budget is a primary concern
- • You need more capabilities (vision, audio)
- • You're already using OpenAI's API ecosystem
Choose o3-pro 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
GPT-5.1 (OpenAI)
o3-pro (OpenAI)
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