gpt-oss-20b vs gpt-oss-20b-MXFP4-Q8
Specs, VRAM requirements and download trends — updated 10 November 2026.
openai · A · Open weights
Params
21.5 B
Context
131,072
30d
5.8 M
apache-2.0 · commercial OK
mlx-community · B · Open weights
Params
20.9 B
Context
131,072
30d
171 K
apache-2.0 · commercial OK
Specification comparison
Differences are highlighted; identical values are muted.
| Specification | gpt-oss-20b | gpt-oss-20b-MXFP4-Q8 |
|---|---|---|
| Deployment | Open weights · also via API | Open weights |
| Parameters | 21.5 B | 20.9 B |
| Architecture | GptOssForCausalLM | GptOssForCausalLM |
| Context length | 131,072 | 131,072 |
| Licence | apache-2.0 | apache-2.0 |
| Commercial use | Allowed | Allowed |
| Languages | — | — |
| Downloads 30d | 5,830,063 | 170,659 |
| Downloads all time | 108.5 M | 7.9 M |
| Quantizations on the Hub | SAFETENSORS | SAFETENSORS |
| Gated | No | No |
| First seen on the Hub | 2025-08-04 | 2025-08-29 |
| API input price / 1M tokens | $0.03 | not on OpenRouter |
| API output price / 1M tokens | $0.13 | not on OpenRouter |
| Est. cost per 1M input + 1M output tokens | $0.16 | not on OpenRouter |
| Cached input / 1M tokens | $0.03 | not on OpenRouter |
| AA Intelligence Index | — | not on OpenRouter |
| AA Coding Index | 20.7 | not on OpenRouter |
| AA Agentic Index | 1.2 | not on OpenRouter |
| Max output tokens | 117,964 | not on OpenRouter |
| API providers | 10 | not on OpenRouter |
| Tool calling | Yes | not on OpenRouter |
| Reasoning mode | Yes | not on OpenRouter |
API cost
Estimated cost of 1M input + 1M output tokens via OpenRouter
gpt-oss-20b
$0.16
Download trend
Daily snapshots, last 90 days (13 Aug – 10 Nov)
8.1 M155 K
gpt-oss-20b
gpt-oss-20b-MXFP4-Q8
VRAM side by side
On RTX 4090 · 24 GB · 8K context unless noted
gpt-oss-20b-MXFP4-Q8 · fp16 @ 128K ctx
64.0 GB / 24 GB
gpt-oss-20b · fp16 @ 128K ctx
82.4 GB / 24 GB