Model benchmarks

gpt-oss:20b local LLM performance

As of August 2026, gpt-oss:20b runs at up to 155.2 tok/s for local inference (best of 30 community benchmark runs across 8 GPUs).

LM StudioOllamaMXFP4
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Model size

20.9B

Peak speed

155.2 tok/s

Average speed

76.4 tok/s

Min memory

9.8 GB

Max context

256,000 tokens

Avg output / run

6,412 tokens

Avg runtime / run

9m 32s

Avg quality

69.5

Benchmark runs

30

GPUs tested

8

Quality by task

Average LLM-judged quality (0–100) with the run-to-run spread shown as a P5–P95 band, overall and for each benchmark task, across all 30 runs. The low and high columns show how much the judge’s score varies between runs, and need at least two runs to display.

TaskP5 (low)AvgP95 (high)
Overall55.769.576.2
Agent Workflow37.676.890.4
Code Generation39.661.577.2
Role Play & Narrative55.166.976.3
Research & Analysis58.872.781.8

Performance by hardware and tool

Every hardware/tool/quantization combination gpt-oss:20b has been benchmarked on, ranked by peak token generation speed. Last updated August 2026.

HardwareToolQuantBest tok/sAvg tok/sMemoryContextQualityRuns
NVIDIA GeForce RTX 4070 Ti SUPERLM Studio155.2 tok/s151.7 tok/s11.3 GB16,384 tokens70.82
NVIDIA L40SOllamaMXFP4120.7 tok/s120.7 tok/s12.0 GB8,192 tokens76.51
AMD Radeon RX 7900 XTXLM Studio111.1 tok/s109.1 tok/s9.8 GB256,000 tokens67.09
AMD Radeon RX 7900 XTXOllamaMXFP470.6 tok/s62.0 tok/s13.1 GB65,536 tokens73.511
NVIDIA GeForce RTX 5080OllamaMXFP464.0 tok/s35.0 tok/s13.3 GB65,536 tokens62.42
Apple M5LM Studio45.3 tok/s45.3 tok/s9.8 GB8,192 tokens74.01
NVIDIA GeForce RTX 5070LM Studio34.8 tok/s34.8 tok/s11.3 GB65,536 tokens72.81
Apple M1 ProOllamaMXFP431.1 tok/s31.1 tok/s11.9 GB8,192 tokens40.71
NVIDIA GeForce RTX 5070OllamaMXFP415.4 tok/s15.4 tok/s14.6 GB65,536 tokens68.21
Apple M3OllamaMXFP48.4 tok/s8.4 tok/s13.0 GB8,192 tokens74.31

Frequently asked questions

Is gpt-oss:20b good for coding?
In our benchmarks, gpt-oss:20b scores 61.5/100 for coding. It runs at about 76.4 tok/s, so if you want more speed, Gemma4:E2B/QAT-MTP@131K is faster (~303.9 tok/s) and still scores well for coding (66.9/100).
Is gpt-oss:20b good for agentic (tool-using) tasks?
In our benchmarks, gpt-oss:20b scores 76.8/100 for agentic workflows. It runs at about 76.4 tok/s, so if you want more speed, Gemma4:E2B/QAT-MTP@131K is faster (~303.9 tok/s) and still scores well for agentic workflows (71.7/100).
How fast is gpt-oss:20b for local inference?
Across 30 community benchmark runs, gpt-oss:20b reaches up to 155.2 tok/s and averages 76.4 tok/s, with the fastest results on NVIDIA GeForce RTX 4070 Ti SUPER.
How much memory does gpt-oss:20b need?
The leanest observed configuration used about 9.8 GB of memory (quantizations tested: MXFP4).
Which tools have been used to run gpt-oss:20b?
Benchmarks were submitted using LM Studio, Ollama. Results are community-contributed and updated as new runs arrive.