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OpenAI Released August 5, 2025 Synced Apr 19, 2026

OpenAI: gpt-oss-20b (free)

gpt-oss-20b is an open-weight 21B parameter model released by OpenAI under the Apache 2.0 license. It uses a Mixture-of-Experts (MoE) architecture with 3.6B active parameters per forward pass, optimized for...

Tool useReasoning

Why it stands out

131K-token context window handles longer documents and multi-turn conversations without truncation.
Combines tool use with reasoning — a strong baseline for agentic and multi-step workflows.
$0/M input makes it practical for always-on agents, batch processing, or high-volume classification.

What to watch

Text-only input — image or audio workflows require a separate model in the pipeline.
No benchmark score currently tracked — evaluate using task-specific testing alongside pricing and capability data.

Release timeline

Tracked events for OpenAI: gpt-oss-20b (free).

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release

OpenAI: gpt-oss-20b (free) entered the tracked catalog

August 5, 2025

gpt-oss-20b is an open-weight 21B parameter model released by OpenAI under the Apache 2.0 license. It uses a Mixture-of-Experts (MoE) architecture with 3.6B active parameters per forward pass, optimized for lower-latency inference and deployability on consumer or single-GPU hardware. The model is trained in OpenAI’s Harmony response format and supports reasoning level configuration, fine-tuning, and agentic capabilities including function calling, tool use, and structured outputs.

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Recent changes

LaunchAug 5

OpenAI launched OpenAI: gpt-oss-20b (free)

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