Standard tierHistoric first

OpenAI gpt-oss-20b

OpenAI · GPT-OSS

OpenAI's first commercially-licensed open-weight model — a historic release under Apache 2.0. MoE architecture keeps only 3.6B parameters active at inference, so it generates tokens at nearly 7B speed despite 20B total params. Supports function calling and web browsing. Over 10M downloads across Ollama and HuggingFace. Pull it with ollama run gpt-oss:20b.

Params

20B total / 3.6B active (MoE)

License

Apache 2.0

Context

128K

Min VRAM

12 GB

Min RAM

16 GB

Tier

Standard

Run locally with Ollama

terminal
ollama run gpt-oss:20b

Once running, Ollama exposes an OpenAI-compatible endpoint at localhost:11434/v1.

Will it run on my hardware?

OpenAI gpt-oss-20b needs about 12 GB of fast memory at Q4. Here is what in our hardware database clears that bar.

Runs at full speed · 12

NVIDIA RTX 5090 32GB32 GB VRAM~$2,999Amazon
NVIDIA RTX 5080 16GB16 GB VRAM~$1,250Amazon
NVIDIA RTX 5070 Ti 16GB16 GB VRAM~$999Amazon
NVIDIA RTX 4060 Ti 16GB16 GB VRAM~$424Amazon
NVIDIA RTX 4070 Super 12GB12 GB VRAM~$734Amazon
NVIDIA RTX 4080 Super 16GB16 GB VRAM~$1,000Amazon
NVIDIA RTX 4090 24GB24 GB VRAM~$2,755Amazon
AMD RX 7900 XTX 24GB24 GB VRAM~$1,339Amazon
Apple Mac mini M4 (16 GB)16 GB unified$799Amazon
Apple Mac mini M4 Pro (24 GB)24 GB unified$1,599Amazon
Apple Mac mini M4 Pro (48 GB)48 GB unified$2,099Amazon
Apple Mac Studio M4 Max (64 GB)64 GB unified$2,899Amazon

Runs, but slower on shared memory · 3

MINISFORUM AI X1 Pro32 GB DDR5 (shared)~$699Amazon
Corsair Vengeance 64 GB DDR5 Kit64 GB DDR5~$1,150Amazon
G.Skill Trident Z5 128 GB DDR5128 GB DDR5~$2,200Amazon

Hardware links are affiliate links. We earn a small commission if you buy through them — at no extra cost to you. Disclosure

Specifications

Parameters20B total / 3.6B active (MoE)
Active params (MoE)3.6B active per token
Context window128K
LicenseApache 2.0
Min VRAM (Q4)12 GB
Min RAM16 GB
Recommended tierStandard
Best forchatcodingreasoningtool use

Variants on Ollama

Ollama serves the Q4_K_M quantization by default. Higher-precision tags exist for users with more memory.

OpenAI gpt-oss-20b

default · Q4_K_M
ollama run gpt-oss:20b
higher precision · q8_0 (generic tag)
ollama pull gpt-oss:q8_0
full precision · fp16 (generic tag)
ollama pull gpt-oss:fp16

Exact quantization tags vary per model — run ollama show gpt-oss or check the tags page for the full list.

Popularity trend (illustrative)

Illustrative adoption trend, not actual download counts. We do not publish a download number for any model because we have no honest source for it.

Similar models