GPT OSS 20B

The GPT OSS 20B is an open-weight language model engineered to deliver high-level reasoning and agentic capabilities in a compact, efficient package. With 21 billion total parameters and 3.6 billion active parameters, it is specifically optimized for lower latency and local inference, making it suitable for edge devices with as little as 16 GB of memory. The model is designed to support complex agentic workflows, including robust function calling and few-shot tasks, while offering users the ability to adjust reasoning effort levels to balance performance with speed requirements.

Built using a combination of reinforcement learning and techniques derived from advanced frontier systems, this model is trained on the harmony response format to ensure consistent and reliable output. Its design emphasizes transparency through full chain-of-thought access, allowing developers to debug and verify the model's reasoning process. By providing a permissive Apache 2.0 license, the model encourages experimentation and commercial deployment, serving as a versatile tool for developers who need to integrate sophisticated reasoning into specialized or on-device applications without relying on heavy infrastructure.

Cloudflare Workers AI@cf/openai/gpt-oss-20bgpt-oss

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Provider: Cloudflare Workers AI
Model key: @cf/openai/gpt-oss-20b
Release date: Aug 5, 2025
Last updated: Aug 5, 2025
Input modalities
Output modalities
Capabilities

Cost

Input token cost: $0.20
Output token cost: $0.30

Limits

Output tokens: 16,384 tokens
Context window: 128,000 tokens

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Rates are shown per one million tokens. Combined means one million input plus one million output tokens.

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Latest news about GPT OSS 20B

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CoverageBenchmark

A third-party benchmark aggregator provides evaluation data for OpenAI's gpt-oss-20b, including results on the AstroMind aerospace reasoning benchmark, where the model achieved 64.6% intent inference accuracy and produced the strongest judged reasoning quality while extracting 136 of 241 scalar values for maneuver para The aggregator's coverage includes comparative model listings and pricing rows showing $0.029 per million input tokens and $0.14 per million output tokens for gpt-oss-20b alongside entries for other contemporary models. Note that some comparison model labels in the scraped excerpt appear garbled or speculative, and the

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Coverage

OpenAI released the open-weight model gpt-oss-20b on August 5, 2025, marking the company's first open-weight large language model release since GPT-2, according to a Baidu encyclopedia entry summarizing the launch. The model uses a Mixture-of-Experts (MoE) Transformer architecture with 21 billion total parameters and 3 Beyond the initial release, the Baidu entry documents downstream ecosystem adoption: Microsoft made gpt-oss-20b available to Windows 11 users via the Windows AI Foundry platform on August 6, 2025, and SiliconFlow launched it internationally on August 19, 2025. A 2026 academic study from institutions including the Unive