gpt-oss-20b (free)

OpenAI chatreasoningtool_use Free

API ID: openai/gpt-oss-20b

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Input Price
Free
/1M tokens
Output Price
Free
/1M tokens

About 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...

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Price Ranking
#6 lowest price among 1240 Chat models — Top 20% cheapest!

Model Specifications

Context Length
131k
Max Output
33k
Release Date
2025-08-05
Capabilities
chat reasoning tool_use
Input Modalities
text
Output Modalities
text

Best For

  • Complex reasoning, math problems, multi-step logic
  • Conversations, content writing, general assistance

Consider Alternatives For

  • Image understanding (needs vision capability)
  • Simple Q&A (cheaper models available)
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This model is completely free!

No token costs - use it without worrying about API bills.

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🚀 Quick Start

Get started with gpt-oss-20b (free) API

OpenAI Python SDK 
from openai import OpenAI
client = OpenAI()

response = client.chat.completions.create(
    model="openai/gpt-oss-20b",
    messages=[
        {"role": "user", "content": "Hello!"}
    ]
)
print(response.choices[0].message.content)

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