ZeroTwo home

GPT 5.5

Default
GPT-5.5 is an OpenAI reasoning model for complex coding, research, and multi-step analysis with a 1M token context window.
GPT-5.5 is an OpenAI reasoning model for complex coding, research, and multi-step analysis with a 1M token context window.

GPT 5.5 is an AI model from OpenAI, available on ZeroTwo. It costs $5.00 per million input tokens and $30.00 per million output tokens, has a 1,050,000-token context window, can return up to 128,000 output tokens, and has a knowledge cutoff of December 1, 2025.

Price
$5.00 • $30.00
Input • Output

GPT-5.5 is an OpenAI reasoning model for complex coding, research, and multi-step analysis with a 1M token context window.

1,050,000 context window
128,000 max output tokens
December 1, 2025 knowledge cutoff
Reasoning token support
Pricing
Pricing is based on the number of tokens used. For tool-specific models, like search and computer use, there's a fee per tool call. See details in the pricing page.

Requests above 272,000 input tokens move the whole request to long-context rates: $10.00 input and $45.00 output per million tokens.

Text tokens
Per 1M tokens
∙
Batch API price
Input
$5.00
Cached input
Output
$30.00
Quick comparison
Input
Cached input
Output
GPT 5.5
$5.00

Questions

How much does GPT 5.5 cost?

GPT 5.5 is priced at $5.00 per million input tokens and $30.00 per million output tokens. On ZeroTwo it is included in your plan's credits rather than billed per token.

What is GPT 5.5's context window?

GPT 5.5 accepts up to 1,050,000 tokens of context and can return up to 128,000 output tokens.

What is GPT 5.5's knowledge cutoff date?

GPT 5.5 has a training knowledge cutoff of December 1, 2025. For anything later than that, use a model with web search enabled.

Can I use GPT 5.5 for free?

You can try GPT 5.5 on ZeroTwo's free plan, which includes a monthly credit allowance across every model in the catalogue. Heavier use moves to a paid plan rather than a per-token bill.