GPT-5.5 Pro
OpenAI
- Context window
- 1M 1,050,000 tokens
- Max output
- 128K 128,000 tokens
- Input / Output
- text, image → text
Timeline
- · Product update · evidence link · evidence link
- · API availability · evidence link · evidence link
Input / output price · USD / 1M tokens
| Model | Evidence links | Input / output price |
|---|---|---|
gpt-5.5-probatch · short context | openai API route unavailable | $15.00 (Input ≤ 272,000 tokens) / $90.00 (Input ≤ 272,000 tokens) |
gpt-5.5-proflex · short context | openai API route unavailable | $15.00 (Input ≤ 272,000 tokens) / $90.00 (Input ≤ 272,000 tokens) |
gpt-5.5-prostandard · long context | openai API route unavailable | $60.00 (Input > 272,000 tokens) / $270.00 (Input > 272,000 tokens) |
gpt-5.5-prostandard · short context | openai API route unavailable | $30.00 (Input ≤ 272,000 tokens) / $180.00 (Input ≤ 272,000 tokens) |
- · Confirmed use · OpenAI · official articles · Introducing GPT-5.5
- · Evidence links · OpenAI · official articles
Excerpt
We’ll bring GPT‑5.5 and GPT‑5.5 Pro to the API very soon
- · Catalogue listing · GitHub · openai/openai-node · code
Excerpt
3-pro' | 'o3-pro-2025-06-10' | 'o3-deep-research' | 'o3-deep-research-2025-06-26' | 'o4-mini-deep-research' | 'o4-mini-deep-research-2025-06-26' | 'computer-use-preview' | 'computer-use-preview-2025-03-11' | 'gpt-5.5-pro' | 'gpt-5.5-pro-2026-04-23' | 'gpt-5-codex' | 'gpt-5-pro' | 'gpt-5-pro-2025-10-06' | 'gpt-5.1-codex-max' | 'gpt-daybreak-blue-latest' | 'gpt-daybreak-red-latest' | 'gpt-5.6-cyber' | 'gpt-6-cyber' | 'gpt-rosalind-research' | 'gpt-6-rosalind' | (string & {}); /** * The object type of this resource - always set to `response`. */ object: 'response'; /** * An array of content items generated by the model. * * - The length and order of items in the `output` array is dependent on the * model's response. * - Rather than accessing the first item in the `output` a
- · Catalogue listing · GitHub · openai/openai-agents-python · code
Excerpt
int] = { **_model_context_windows( ( "gpt-5.4", "gpt-5.4-2026-03-05", "gpt-5.4-pro", "gpt-5.4-pro-2026-03-05", "gpt-5.5", "gpt-5.5-2026-04-23", "gpt-5.5-pro", "gpt-5.5-pro-2026-04-23", "gpt-5.6", "gpt-5.6-sol", "gpt-5.6-terra", "gpt-5.6-luna", "gpt-4.1", "gpt-4.1-2025-04-14", "gpt-4.1-mini", "gpt-4.1-mini-2025-04-14", "gpt-4.1-nano", "gpt-4.1-nano-2025-04-14", ), 1_047_576, ), **_model_context_windows( ( "gpt-5", "gpt-5-2025-08-07", "gpt-5-codex", "gpt-5-mini", "gpt-5-mini-2025-08-07", "gpt-5-nano", "gpt-5-nano-2025-08-07", "gpt-5
- · Catalogue listing · GitHub · openai/openai-python · code
Excerpt
-deep-research", "o3-deep-research-2025-06-26", "o4-mini-deep-research", "o4-mini-deep-research-2025-06-26", "computer-use-preview", "computer-use-preview-2025-03-11", "gpt-5.5-pro", "gpt-5.5-pro-2026-04-23", "gpt-5-codex", "gpt-5-pro", "gpt-5-pro-2025-10-06", "gpt-5.1-codex-max", "gpt-daybreak-blue-latest", "gpt-daybreak-red-latest", "gpt-5.6-cyber", "gpt-6-cyber", "gpt-rosalind-research", "gpt-6-rosalind", ], str, None, ] = None """Model ID used to generate the response, like `gpt-6-astra`. OpenAI offers a wide range of models with different capabilities, performance characteristics, and price points. Refer to the [model guide](https
Signals 1
Specifications
GPT-5.5 Pro is a model from OpenAI, released on 23 Apr 2026. The context window is 1,050,000 tokens. The maximum output is 128,000 tokens.
- Context window
- 1,050,000
- Max output
- 128,000
- Input
- text · image
- Output
- text
Questions
What is the context window of GPT-5.5 Pro?
The context window is 1,050,000 tokens. The maximum output is 128,000 tokens.
When was GPT-5.5 Pro released?
On 23 Apr 2026.