GPT-4 Turbo (128K)
GPT-4 Turbo with 128K context is OpenAI's extended-context variant of GPT-4, designed to process very long documents, codebases, or conversation histories in a single pass. The 128K token window allows ingestion of book-length texts, lengthy legal contracts, or large code repositories without fragmentation, making it practical for tasks that would otherwise require chunking strategies.
Beyond context length, GPT-4 Turbo brings improved instruction following and lower latency compared to the original GPT-4. OpenAI positioned it as the cost-optimized high-capability choice for applications needing both reasoning depth and extended input capacity.
Key Features
128K token context window for processing long documents in a single request
Strong reasoning and instruction-following derived from the GPT-4 architecture
JSON mode and function-calling support for structured output pipelines
Improved factual accuracy and reduced verbosity versus GPT-4 base
Multimodal input support (text and images) in supported API configurations
Ideal Use Cases
Legal contract review and clause extraction across lengthy documents
Codebase-level analysis and refactoring with full file context
Long-form research synthesis from large sets of source documents
Extended customer support conversations with full session history
Example Prompts for GPT-4 Turbo (128K)
Technical Specifications
| Provider | OpenAI |
| Category | Text |
| Modality | Text -> Text |
| Context Window | 128,000 tokens |
Frequently Asked Questions
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