Compare · ModelsLive · 2 picked · head to head

gpt-oss-20b vs GPT-5 Nano

Side by side · benchmarks, pricing, and signals you can act on.

Winner summary

GPT-5 Nano wins 4 of 5 shared benchmarks. Leads in knowledge · language · reasoning.

Category leads
knowledge·GPT-5 Nanolanguage·GPT-5 Nanomath·gpt-oss-20breasoning·GPT-5 Nano
Hype vs Reality
gpt-oss-20b
#24 by perf·no signal
QUIET
GPT-5 Nano
#114 by perf·no signal
QUIET
Best value
3.9x better value than GPT-5 Nano
gpt-oss-20b
792.9 pts/$
$0.09/M
GPT-5 Nano
201.3 pts/$
$0.23/M
Vendor risk
OpenAI logo
OpenAI
$840.0B·Tier 1
Medium risk
OpenAI logo
OpenAI
$840.0B·Tier 1
Medium risk
Head to head
gpt-oss-20bGPT-5 Nano
HELM · GPQA
GPT-5 Nano leads by +8.5
gpt-oss-20b
59.4
GPT-5 Nano
67.9
HELM · IFEval
GPT-5 Nano leads by +20.0
gpt-oss-20b
73.2
GPT-5 Nano
93.2
HELM · MMLU-Pro
GPT-5 Nano leads by +3.8
gpt-oss-20b
74.0
GPT-5 Nano
77.8
HELM · Omni-MATH
gpt-oss-20b leads by +1.8
gpt-oss-20b
56.5
GPT-5 Nano
54.7
HELM · WildBench
GPT-5 Nano leads by +6.9
gpt-oss-20b
73.7
GPT-5 Nano
80.6
Full benchmark table
Benchmarkgpt-oss-20bGPT-5 Nano
HELM · GPQA
59.467.9
HELM · IFEval
73.293.2
HELM · MMLU-Pro
74.077.8
HELM · Omni-MATH
56.554.7
HELM · WildBench
73.780.6
Pricing · per 1M tokens · projected $/mo at 10M tokens
ModelInputOutputContextProjected $/mo
OpenAI logogpt-oss-20b$0.03$0.14131K tokens (~66 books)$0.57
OpenAI logoGPT-5 Nano$0.05$0.40400K tokens (~200 books)$1.38