GPT-5.5
Flagshipby OpenAI
GPT-5.5 is OpenAI's newest flagship model, the first fully retrained base since GPT-4.5. It features a 1M token context window, native omnimodal capabilities, and leads the Artificial Analysis Intelligence Index. At $5 per million input tokens, it doubles GPT-5.4 pricing while delivering substantially higher benchmark scores.
Input Price
$5.00
per 1M tokens
Output Price
$30.00
per 1M tokens
Context Window
1M
tokens
Released
2026-04
API access
Capabilities
Key Strengths
- ✓Top benchmark scores
- ✓1M token context
- ✓Natively omnimodal
- ✓40% fewer tokens than GPT-5.4
Best For
- ▸Complex reasoning and research
- ▸Full codebase analysis
- ▸Advanced agentic workflows
- ▸Multimodal processing
Benchmark Scores
| Benchmark | Score | Description |
|---|---|---|
| MMLU-Pro | 94.2 | General knowledge and reasoning across 57 subjects |
| HumanEval | 97.1 | Python code generation and problem solving |
| GPQA Diamond | 78.3 | Graduate-level science questions verified by domain experts |
| MATH | 95.8 | Competition-level mathematics problems |
| SWE-bench | 68.7 | Real-world software engineering tasks from GitHub issues |
Scores sourced from public benchmark datasets. See full benchmark leaderboard for all models.
Pricing Details
Input tokens
$5.00
per 1M tokens
Output tokens
$30.00
per 1M tokens
Estimated cost per 1K requests
$20.00
~1K input + ~500 output tokens avg
Prices are subject to change. Check the official documentation for current pricing. See the cost calculator for detailed estimates.
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