GPT-5.5 Pro

OpenAI

High-end reasoning tier of GPT-5.5 for the most difficult tasks.

Text Generation API GPT Family v5.5

Documentation Back to Models

Parameters

-

params

Context Window

1.0M

tokens

Max Output

-

tokens

Input Price

$30

per 1M tokens

Output Price

$180

per 1M tokens

GPT Family 18 models

The full GPT line by generation — pricing and capabilities vary across the family.

GPT-5.5

GPT-5.5 Instant

Everyday assistant, low-latency chat

GPT-5.5 Pro Current

Hardest reasoning, research, complex coding

$30 / $180

in / out · 1M

Apr 2026

Agentic workflows, coding, research, data analysis

GPT-5.4

Complex reasoning, research, advanced analysis

General-purpose, reasoning, multimodal, document editing

GPT-5.3

Code generation, software engineering, reasoning

GPT-5

GPT-5.2 Thinking

GPT-5.2 Instant

Multimodal reasoning, reduced hallucinations

GPT-5.1

GPT-5.1 Instant

Fast, warm responses, customizable tone

GPT-5.1 Thinking

Complex reasoning, persistent problem-solving

GPT-4

GPT-4o (Nov 2024)

Multimodal, fast, versatile

Complex tasks, vision, analysis

Enterprise Azure integration

o1

Complex reasoning, math, code

STEM reasoning, efficient

GPT-3.5

Fast, cost-effective

Capabilities

👁️

Vision

⚡

Function Calling

📋

JSON Mode

🌊

Streaming

💬

System Prompt

🖥️

Code Execution

🔍

Web Search

🔌

MCP Support

Details

Release Date: April 24, 2026
Knowledge Cutoff: December 1, 2025
Source: API
API Key Required: Yes
License: Proprietary
Model ID: gpt-5.5-pro

Last updated: May 27, 2026