GPT-5.5 Pro vs o3
GPT-5.5 Pro vs o3: o3 is cheaper for input-heavy usage ($2.00/M vs $30.00/M input tokens), while GPT-5.5 Pro is better for long-context tasks (1,050,000 tokens).
Direct answer: choose o3 for lower token spend and choose GPT-5.5 Pro when your workload needs longer context.
Common pricing searches covered on this page: GPT-5.5 Pro vs o3 • GPT-5.5 Pro vs o3 pricing • GPT-5.5 Pro vs o3 API pricing and 5 5 pro vs o3 pricing.
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
GPT-5.5 Pro
o3
Cost Differences
o3 costs less than GPT-5.5 Pro
Quick Recommendation
Winner for direct API pricing: o3. At the default workload, o3 saves about $342.00/month ($4,161.00/year) versus GPT-5.5 Pro.
Feature Comparison
| Feature | GPT-5.5 Pro | o3 |
|---|---|---|
| Provider | OpenAI | OpenAI |
| Input Price | $30.00/1M tokens | $2.00/1M tokens |
| Output Price | $180.00/1M tokens | $8.00/1M tokens |
| Context Window | 1,050,000 tokens | 1,000,000 tokens |
| Max Output | 128,000 tokens | 131,072 tokens |
| Category | reasoning | reasoning |
| Capabilities | textvisioncodereasoning | textreasoningvisioncode |
| Release Date | 4/24/2026 | 4/16/2025 |
GPT-5.5 Pro vs o3: Which Should You Choose?
Choosing between GPT-5.5 Pro and o3 depends on your priorities: cost efficiency, context length, or raw capability. o3 is the more affordable option at $2.00/1M input tokens — 93% cheaper than GPT-5.5 Pro. Meanwhile, GPT-5.5 Pro offers a significantly larger context window at 1,050,000 tokens vs 1,000,000 for o3.
Both models are in the reasoning category, making this a direct head-to-head comparison. At scale — say 10,000 requests per day — the cost difference adds up: o3 would save you roughly $34,200.00/month compared to GPT-5.5 Pro. For startups and indie developers, that difference can be significant.
Output costs matter too. GPT-5.5 Pro charges $180.00/1M output tokens vs $8.00 for o3. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. o3 has the edge here at $8.00/1M 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 GPT-5.5 Pro when:
- • You need a larger context window (1,050,000 tokens)
- • You're already using OpenAI's API ecosystem
Choose o3 when:
- • Budget is a primary concern
- • You need longer outputs (up to 131,072 tokens)
- • You're already using OpenAI's API ecosystem
Pros and Caveats at a Glance
GPT-5.5 Pro
- • Input pricing: $30.00/M tokens
- • Output pricing: $180.00/M tokens
- • Context window: 1,050,000 tokens
- • Max output: 128,000 tokens
Watch out for
- • Higher input cost than o3
- • Higher output cost than o3
o3
- • Input pricing: $2.00/M tokens
- • Output pricing: $8.00/M tokens
- • Context window: 1,000,000 tokens
- • Max output: 131,072 tokens
Watch out for
- • Smaller context window than GPT-5.5 Pro
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
GPT-5.5 Pro (OpenAI)
o3 (OpenAI)
Start using GPT-5.5 Pro today
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Sign Up for OpenAI →Frequently Asked Questions
Which is cheaper, GPT-5.5 Pro or o3?▼
What is the context window difference between GPT-5.5 Pro and o3?▼
Which model is better for AI Agent / Agentic Workflows?▼
Which model has better overall pricing for heavy usage?▼
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