OpenAI

GPT-5.5 (batch)

by OpenAItext+image+file->text1 endpoint

Overview

GPT-5.5 is OpenAI’s frontier model designed for complex professional workloads, building on GPT-5.4 with stronger reasoning, higher reliability, and improved token efficiency on hard tasks. It features a 1M+ token context window (922K input, 128K output) with support for text and image inputs, enabling large-scale reasoning, coding, and multimodal workflows within a single system.

Capabilities

Text generation
Image understanding
Tool use / Function calling
Structured output
Extended reasoning
Prompt caching
Long context
File input
Deterministic seed

Modalities

Input
FileImageText
Output
Text

Technical Specifications

Context Window
1.1M tokens
Max Output
128K tokens
Knowledge Cutoff
2025-12-01
Tokenizer
GPT
Content Moderation
Enabled

Supported Parameters

include_reasoningmax_tokensreasoningreasoning_effortresponse_formatseedstructured_outputstool_choicetools

Pricing

Per 1M tokens
Input$2.50
Output$15.00
Cache read$0.25
Added
April 24, 2026
Last synced 9/21/2026