gpt-oss-20b (free)
by OpenAI
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 f
Models
gpt-oss-20b (free)
Added 10 July 2026
Overview
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...
How to use / API access
Call via OpenRouter with model id `openai/gpt-oss-20b:free`.
- openrouter ·
openai/gpt-oss-20b:freeDocs
OpenRouter id: openai/gpt-oss-20b:free
Benchmarks
- Intelligence Index (artificial-analysis) : 14.9 index
- Coding Index (artificial-analysis) : 20.7 index
- Agentic Index (artificial-analysis) : 3.1 index
- Design Arena dataviz (other) : 969 elo · #98
- Design Arena website (other) : 883 elo · #113
Notes
gpt-oss-20b (free) is listed in the EDNA Models directory from the OpenRouter catalogue.
Get the free Developer’s Field Guide
A 27-page field guide to the AI coding workflow with Claude. Claude Code, MCP servers, the prompt patterns that work, and what to delegate. Free.
Enter your work email. We send it straight over, plus a few short notes worth knowing. Unsubscribe any time.