GPT-5.5
Flagshipby OpenAI
As of October 19, 2026, GPT-5.5 by OpenAI costs $5.00 per 1M input tokens and $30.00 per 1M output tokens, with a 1M-token context window. It ranks 11th of 29 models on the TensorFeed Intelligence Index's older 2024 benchmark set, with a score of 69.8 (as of October 22, 2026).
GPT-5.5 was OpenAI's flagship from April 2026 until the GPT-5.6 family (Sol, Terra, and Luna) reached general availability on July 9, 2026, and it was 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 |
|---|---|---|
| SWE-bench | 82.6 | Real-world software engineering tasks from GitHub issues (SWE-bench Verified) |
| 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 |
| FrontierCode v1.1 | 43.0 | Agentic coding on frontier software engineering tasks (Main split) |
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.
Quick answers
- How much does GPT-5.5 cost?
- As of October 19, 2026, GPT-5.5 costs $5.00 per 1M input tokens and $30.00 per 1M output tokens on the OpenAI API.
- What is the context window of GPT-5.5?
- GPT-5.5 has a 1M-token context window (1,000,000 tokens).
- How does GPT-5.5 rank on the TensorFeed Intelligence Index?
- GPT-5.5 ranks 11th of 29 models on the TensorFeed Intelligence Index's older 2024 benchmark set, with a score of 69.8 (as of October 22, 2026). Scores from the 2024 and 2026 benchmark sets are ranked separately and never compared.
Embed the TFII badge
A live badge with this model's TensorFeed Intelligence Index rank and score. It updates with the daily index and links to the ranking.
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