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GPT Opensources 20B
GPT Opensources 20B is a reasoning model developed by OpenAI. It has approximately 210.0B parameters and is an open foundational model that supports a 128K context window.
Parameters
210.0B
Context Window
128K
License
Apache 2.0
Release Date
2025-08-06
API Pricing
API pricing for this model is not yet available
Strengths
- ・Possesses advanced reasoning ability
- ・128K long context support
- ・Open Apache 2.0 license
Weaknesses
- ・Large file size of 42GB
- ・Requires substantial computational resources
- ・Massive 210.0B parameter count
Use Cases
- ・Complex logical reasoning tasks
- ・Long document analysis
- ・Open-source AI development
Deep Analysis
Release Date
August 5, 2025
Parameters
21B
License
Apache 2.0
AIME 2025
98.70%
GPQA Diamond
74.20%
SWE-bench
60.70%
Pricing
$0.04-$0.075 / $0.15-$0.30 per 1M tokens
Strengths
- ・Fully open-source Apache 2.0
- ・Exceptional math (AIME 98.70%)
- ・Very cheap
- ・Self-hostable on consumer hardware
Weaknesses
- ・GPQA (74.20%) lower than GPT-5 series
- ・Text-only
Competitor Comparison
| Model | SWE | Price |
|---|---|---|
| GPT-5 Nano | 34.8% | $0.05/$0.40 |
| Llama 3.1 405B | $0.80/$0.80 |
gpt-oss-20b is OpenAI's first open-weight model under Apache 2.0. Exceptional math at AIME 98.70%.
Sources
Analysis generated: 2026-05-24