Compare · ModelsLive · 2 picked · head to head
gpt-oss-120b vs gpt-oss-20b
Side by side · benchmarks, pricing, and signals you can act on.
Winner summary
gpt-oss-120b wins on 6/6 benchmarks
gpt-oss-120b wins 6 of 6 shared benchmarks. Leads in arena · knowledge · language.
Category leads
arena·gpt-oss-120bknowledge·gpt-oss-120blanguage·gpt-oss-120bmath·gpt-oss-120breasoning·gpt-oss-120b
Hype vs Reality
Attention vs performance
gpt-oss-120b
#106 by perf·no signal
gpt-oss-20b
#22 by perf·no signal
Best value
gpt-oss-20b
1.9x better value than gpt-oss-120b
gpt-oss-120b
409.6 pts/$
$0.11/M
gpt-oss-20b
792.9 pts/$
$0.09/M
Vendor risk
Who is behind the model
OpenAI
$840.0B·Tier 1
OpenAI
$840.0B·Tier 1
Head to head
6 benchmarks · 2 models
gpt-oss-120bgpt-oss-20b
Chatbot Arena Elo · Overall
gpt-oss-120b leads by +36.1
gpt-oss-120b
1353.8
gpt-oss-20b
1317.7
HELM · GPQA
gpt-oss-120b leads by +9.0
gpt-oss-120b
68.4
gpt-oss-20b
59.4
HELM · IFEval
gpt-oss-120b leads by +10.4
gpt-oss-120b
83.6
gpt-oss-20b
73.2
HELM · MMLU-Pro
gpt-oss-120b leads by +5.5
gpt-oss-120b
79.5
gpt-oss-20b
74.0
HELM · Omni-MATH
gpt-oss-120b leads by +12.3
gpt-oss-120b
68.8
gpt-oss-20b
56.5
HELM · WildBench
gpt-oss-120b leads by +10.8
gpt-oss-120b
84.5
gpt-oss-20b
73.7
Full benchmark table
| Benchmark | gpt-oss-120b | gpt-oss-20b |
|---|---|---|
Chatbot Arena Elo · Overall | 1353.8 | 1317.7 |
HELM · GPQA | 68.4 | 59.4 |
HELM · IFEval | 83.6 | 73.2 |
HELM · MMLU-Pro | 79.5 | 74.0 |
HELM · Omni-MATH | 68.8 | 56.5 |
HELM · WildBench | 84.5 | 73.7 |
Pricing · per 1M tokens · projected $/mo at 10M tokens
| Model | Input | Output | Context | Projected $/mo |
|---|---|---|---|---|
| gpt-oss-120b | $0.04 | $0.19 | 131K tokens (~66 books) | $0.77 |
| gpt-oss-20b | $0.03 | $0.14 | 131K tokens (~66 books) | $0.57 |