GPT OSS 20B
OpenAI's open-weight, 20B-parameter reasoning model for low-latency, local, and agentic use cases — customizable, uncensored, and privacy-first on Venice.
Get API keyWhat is GPT OSS 20B?
GPT OSS 20B is OpenAI's medium-sized open-weight reasoning model, released in August 2025 with 21B parameters and 3.6B active parameters. Designed for low-latency and local deployment, it supports configurable reasoning effort, full chain-of-thought, tool use, and fine-tuning under the permissive Apache 2.0 license.
Use GPT OSS 20B privately on Venice
Running GPT OSS 20B on Venice ensures full sovereignty — your prompts never leave your control. With end-to-end encryption and execution in a Trusted Execution Environment (TEE), Venice guarantees zero retention and private inference. You get the full power of an open, uncensored model without surveillance or data leakage.
What can GPT OSS 20B do?
- •Open weights under Apache 2.0 — no copyleft restrictions, safe for commercial use and fine-tuning.
- •Configurable reasoning effort (low/medium/high) for optimal latency and cost trade-offs.
- •Full chain-of-thought visibility and agentic capabilities: web search, Python execution, and structured outputs.
- •Optimized for local and edge deployment — runs on devices with as little as 16GB memory.
- •Strong performance on reasoning, code, and multilingual tasks despite smaller size.
- •Not uncensored — follows OpenAI’s safety policies by default, limiting certain use cases.
- •Smaller active parameter count may limit depth of reasoning compared to larger models like gpt-oss-120b.
- •No vision or multimodal input support — text-only model.
GPT OSS 20B capabilities
- Tool use / function calling
- Vision (image input)
- Reasoning
- Web search
- Code-optimized
- Structured output (JSON schema)
- Audio input
- Video input
- Multiple image inputs
- Log probabilities
How to use GPT OSS 20B via API
Venice exposes an OpenAI-compatible API. Swap your base URL and call e2ee-gpt-oss-20b-p.
curl https://api.venice.ai/api/v1/chat/completions \
-H "Authorization: Bearer $VENICE_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "e2ee-gpt-oss-20b-p",
"messages": [{ "role": "user", "content": "Explain quantum tunneling simply." }]
}'Specifications
Pricing
Billed per token on Venice: $0.05 per 1M input tokens and $0.19 per 1M output tokens.
New Venice accounts include a free daily allowance and 500 welcome credits — no credit card required.
GPT OSS 20B vs alternatives
| Model | Max context | Open weights | Price (Venice) | Strongest at |
|---|---|---|---|---|
| GPT OSS 20B | 128K tokens | Yes | $0.05 in · $0.19 out / 1M | Local reasoning & tool use |
| Google Gemma 4 31B Instruct | 256K tokens | Yes | $0.12 in · $0.36 out / 1M | Efficient instruction following |
| GLM 5.1 | 200K tokens | Yes | $1.10 in · $4.15 out / 1M | Multilingual reasoning |
| DeepSeek V4 Flash 0731 | 1M tokens | No | $0.17 in · $0.35 out / 1M | High-context throughput |
Open-weight, privacy-first model ideal for on-device and agentic use.
What is GPT OSS 20B good for?
- •On-device AI agents requiring low latency and privacy.
- •Customizable reasoning pipelines in regulated or offline environments.
- •Fine-tuned domain-specific assistants for code, math, or research.
- •Agentic workflows with tool use (web search, code execution) without cloud dependency.
- •Privacy-first enterprise deployments where data sovereignty is mandatory.
Prompting tips
- •Use the 'reasoning_effort' parameter to balance speed and depth — 'low' for quick tasks, 'high' for complex reasoning.
- •Structure prompts to trigger tool use explicitly: 'Search the web for...' or 'Run Python to calculate...'.
- •Leverage full chain-of-thought for debugging — inspect intermediate steps in agentic workflows.
- •Fine-tune for niche domains where proprietary models lack specialization.
Version history
Larger variant with higher reasoning capacity.
CurrentCurrent — optimized for local and low-latency use.
Frequently asked questions
GPT OSS 20B is OpenAI's open-weight, 21B-parameter mixture-of-experts language model released in August 2025. It supports configurable reasoning, tool use, and full chain-of-thought, designed for low-latency, local, and agentic deployments under the Apache 2.0 license.
Yes, GPT OSS 20B is open weights and released under the permissive Apache 2.0 license, allowing free use, modification, and commercial deployment. You can download and run it locally from Hugging Face or via Venice’s private API.
On Venice, GPT OSS 20B is billed per token: $0.05 per 1M input tokens and $0.19 per 1M output tokens. There is no subscription — you pay only for what you use.
Yes, GPT OSS 20B natively supports tool use including web search, Python code execution, and structured outputs, making it ideal for agentic workflows and autonomous tasks.
Yes, GPT OSS 20B is fully fine-tunable under the Apache 2.0 license, allowing developers to customize it for specific domains, tasks, or compliance requirements without restrictions.
GPT OSS 20B excels in agentic reasoning and tool use with configurable effort, while Gemma 4 31B offers stronger base instruction following. GPT OSS 20B is better for dynamic workflows; Gemma may suit static, efficient inference tasks.
No, GPT OSS 20B follows OpenAI’s safety policies by default and is not uncensored. However, its open weights allow developers to modify or fine-tune it for less restrictive behavior, subject to their own policies.
GPT OSS 20B supports a 128K-token context window and can generate up to 32.768K tokens in a single output, making it suitable for long-form reasoning and document processing.
Related models
Run GPT OSS 20B privately.
No prompt logging. No data used for training. Free to start — no credit card.
