gpt-oss-120b
gpt-oss-120b is an open-weight, 117B-parameter Mixture-of-Experts (MoE) language model from OpenAI designed for high-reasoning, agentic, and general-purpose production use cases. It activates 5.1B parameters per forward pass and is optimized to run on a single H100 GPU with native MXFP4 quantization. The model supports configurable reasoning depth, full chain-of-thought access, and native tool use, including function calling, browsing, and structured output generation.
Context window
This model accepts 131K tokens in one request (~98K words of text).
What fits in one request
- FitsShort documentAbout 1,500 words of text
- FitsLong documentAbout 37K words of text
- Won't fitSmall codebaseAbout 150K words of text
- Won't fitFull novelAbout 375K words of text
Specifications
Context size, pricing, and release info in one place.
- Context window
- 131,072 tokens (131K)
- Max output tokens
- 131,072 tokens (131K)
- Speed tier
- balanced
- Provider
- Openai
- Release date
- Aug 2025
- Input cost
- $0.100/M / 1M tokens
- Output cost
- $0.500/M / 1M tokens
Capabilities
See which features this model supports, such as vision, tools, and streaming.
- Tool use
- Can call external tools and APIs
- Supported
- Function calling
- Structured function call interface
- Supported
- Extended thinking
- Shows its chain-of-thought reasoning
- Supported
- Streaming
- Returns tokens as they are generated
- Supported
- Prompt caching
- Reuse repeated prompt prefixes cheaply
- Supported
- Vision
- Accepts image inputs alongside text
- Not supported
- Web search
- Can browse the web during a request
- Not supported
- Batch API
- Process many requests asynchronously
- Not supported
Best for
Jump to a guide or ranking that matches each workload.
Compare gpt-oss-120b
Open a side-by-side comparison with one click.
- gpt-oss-120b vs Amazon Titan Text Express
gpt-oss-120b has 212% larger context window
- gpt-oss-120b vs Amazon Titan Text Lite
gpt-oss-120b has 212% larger context window
- gpt-oss-120b vs Amazon Titan Text Premier
gpt-oss-120b has 212% larger context window
- gpt-oss-120b vs Claude Instant
gpt-oss-120b has 31% larger context window
- gpt-oss-120b vs Anthropic Claude
gpt-oss-120b has 31% larger context window
- gpt-oss-120b vs Codellama 34b Instruct
gpt-oss-120b has 3100% larger context window
Frequently asked questions
Short answers about context size and how this model behaves.
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