gpt-oss-120b

Name: gpt-oss-120b
Author: OpenAI

Catalogue only Open weights

Sovereignty and hosting

Catalogue only

This model is catalogued for reference. It is not hosted on LLM EU yet, and no first-party endpoint serves it here. Requests to it go to the provider directly, under that provider's own terms.

Summary

gpt-oss-120b is OpenAI’s open-weight reasoning model, a mixture-of-experts model with 117B total and 5.1B activated parameters under the Apache-2.0 licence. It runs on a single 80GB GPU because the expert weights are post-trained in MXFP4, and the configuration declares a context window of 131,072 tokens. It must be used with OpenAI’s harmony response format and exposes three reasoning-effort levels.

Specifications

Provider: OpenAI (US)
Context window: 131k
Parameters: 116.83B
Modalities: text
License: apache-2.0 · licence
Open weights: yes
Release date: 05 Aug 2025
Tasks: reasoning, coding, rag, summarization

Languages

Strong: en

Adequate: de, fr, es, it, pt, ja, ko, zh, ar

Languages

Strong

Adequate

Not verified: the provider has not documented this claim. — a language is listed as strong only where a source claims it; the card links the evidence where one exists.

When to use it

Strengths

Apache-2.0 licence with no user threshold
runs on a single 80GB accelerator
configurable reasoning effort with full chain-of-thought access
native function calling, browsing and structured output

Limits

requires the harmony response format; other prompt templates degrade it
117B parameters must be resident even though only 5.1B are active
chain-of-thought output is not intended for end users

Pricing

This model is catalogued for reference. It is not hosted on LLM EU yet, and no first-party endpoint serves it here. Requests to it go to the provider directly, under that provider's own terms.

Verification status

Where a field has no source, the card shows it as unverified instead of filling it in. An empty field is information.

LLM EU Verified means documented, not legally certified. It is not an AI Act conformity assessment and LLM EU is not an EU body.

Versions and variants

catalogue · Catalogue only · weights

Example request

curl https://api.llmeu.com/v1/chat/completions \
  -H "Authorization: Bearer $LLMEU_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"gpt-oss-120b","messages":[{"role":"user","content":"Hello"}]}'

No playground is deployed for this model: no endpoint serves it, so a request would have nowhere to go.

Benchmarks

No published evaluation. This is a gap, not a hidden result.

Sources

Card changelog

05 Aug 2025 — Release date
19 Sept 2026 — Last reviewed

Last reviewed: 19 Sept 2026

Tasks

Reasoning