GPT-OSS
gpt-oss-20b
OpenAI's smaller open-weight MoE release, natively quantized to MXFP4 for the MoE weights.
Total params
21B
Active params
3.6B
Layers
24
Hidden size
2880
Attention heads
64
KV heads (GQA)
8
Vocab size
201,088
Native context window
131,072
Native precision
BF16
Experts (total)
32
Experts active / token
4
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