gpt-oss-20b

gpt-oss-20b

Developer	OpenAI
Release date	August 5, 2025
Family	gpt-oss
Size class
Context window	131K tokens
Max output	118K tokens
Input	Text
Output	Text
Knowledge cutoff	2024-06
Weights	Open weights
Website	openai.com
Links	Model card Docs Hugging Face

Part of a series on

input: $0.03
cached: $0.03
output: $0.13
Context: 131Ktokens
Released: 1y ago
Size: 20Bparameters

Specifications

Model

Developer: OpenAI
Family: gpt-oss
Type: Language model
Released: August 5, 2025
Model ID: openai/gpt-oss-20b

Capabilities

Input → output: Text → Text
Native context: 128K tokens
Max output: 118K tokens
Tokenizer: GPT
Knowledge cutoff: 2024-06

Weights

Openness: Open weights
Size: 20B
Hugging Face: openai/gpt-oss-20b

Lineage

Models built on this: gpt-oss-safeguard-20bfine-tuned from

Sources:models.devOpenRouter

Metadata synced Nov 7, 2026, 9:00 PM UTC

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