OpenAI

OpenAI: gpt-oss-120b (batch)

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...

ReasoningTool callingStreamingJSON mode
131.1K token context Released Aug 5, 2025

Intelligence overview

0
Intelligence
0
Coding
0
Agentic

131.1K tok

Context window

118.0K tok

Max output

Capabilities

What OpenAI: gpt-oss-120b (batch) can do.

Reasoning

Extended reasoning

Works through problems step by step before answering, trading latency for accuracy on harder tasks.

Adjustable effort

Choose how much the model deliberates per request — trade speed for depth as the task demands.

Development

Tool calling

Calls external functions mid-response, then continues reasoning from the result.

Structured output

Returns responses constrained to a JSON schema, ready to parse without cleanup.

Streaming

Streams tokens as they're generated instead of waiting on the full response.

Performance

Intelligence12.3
Artificial Analysis
Coding30.4
Artificial Analysis
Agentic6.2
Artificial Analysis

Design Arena — ranked #106 across 6 categories

Pricing

Pay for what you use.

Every model in UltraGPT runs behind one flat subscription — this is the underlying per-token cost the catalog tracks.

INPUT

$0.15 / 1M tok

OUTPUT

$0.6 / 1M tok

Use cases

Built for serious work.

Build

Generate and refactor code, with the ability to run and verify tool calls and return structured, parseable output.

Think

Works through hard problems with adjustable reasoning effort — high, medium, low.

Research

Holds up to 131.1K tokens of source material in context without losing the thread.

Automate

Chains tool calls across multi-step workflows, reasoning between each one.

Preview

Ask OpenAI: gpt-oss-120b (batch) anything.

A preview of the real UltraGPT composer — the model you see here is the model you get.

OpenAI: gpt-oss-120b (batch) Ready

Continues in the UltraGPT app — one login, every model.

Comparison

How OpenAI: gpt-oss-120b (batch) stacks up.

The closest models in the catalog by provider, capability and score — real entries, pulled from the same directory.

Specification

Technical details.

Specification

Context window
131.1K tokens
Max output
118.0K tokens
Input modalities
Text
Output modalities
Text
Knowledge cutoff
Jun 30, 2024
Release date
Aug 5, 2025
Reasoning effort
high, medium, low (always on)
Streaming
Supported
Tool calling
Supported
JSON mode
Supported

Model identity

Provider
OpenAI
Provider ID
openai

Model ID

Reasoning

Effort: high, medium, low · always on
Directory

More from OpenAI, and everything else.

This model is one entry in the full UltraGPT catalog — browse the rest, compare pricing and context windows, or filter by capability.

OpenAI: gpt-oss-120b (batch), one subscription away.

UltraGPT puts this model — and every other one in the directory — behind a single login and one flat monthly price.