GPT OSS 120B: Price, Context, Benchmarks, and Release Details

OpenAI provisional listing open weights · first seen Oct 8, 2026 · score computed Oct 9, 2026, 01:49 UTC
54.8
SI Score (method si-v3-retained-evidence-2)
#89 of 140 ranked
79% confidence 79 percent, Medium confidence — 5 of 10 expected sources in
Coverage 63% of expected source weight · 100% confidence at 80% coverage

Pillar breakdown

Coding (weight 40 percent) 28.0
Math (weight 15 percent) 88.9
Preference (weight 15 percent) 69.6
Reasoning (weight 30 percent) 75.8

Pillar weights: reasoning 30% · math 15% · coding 40% · preference 15%. Benchmark results use fixed 0–100 scales before averaging; incomplete evidence is shrunk toward 50.

Facts

Input price / 1M
not yet reported
Output price / 1M
not yet reported
Context window
131Kmodels.devPublished source fact Retrieved Oct 9, 2026 · MIT
Open source ↗
Max output
32.8Kmodels.devPublished source fact Retrieved Oct 9, 2026 · MIT
Open source ↗
Released
Aug 5, 2025models.devPublished source fact Retrieved Oct 9, 2026 · MIT
Open source ↗
Open weights
Yesmodels.devPublished source fact Retrieved Oct 9, 2026 · MIT
Open source ↗
License
not yet reported
Input modalities
textmodels.devPublished source fact Retrieved Oct 9, 2026 · MIT
Open source ↗

Benchmark results

6 results
Benchmark Raw result Normalized (0–100) Pillar
aider polyglot 41.8%Aider polyglotPublished source fact [variant] Aider polyglot; 225 cases; 2 attemptsPublished Aug 6, 2025 Retrieved Oct 9, 2026 · Apache-2.0
Open source ↗
41.8 coding
gpqa diamond 75.8%Epoch AI BenchmarkingEpoch-owned evaluation mean score; scores only, no benchmark questions [variant] highPublished Dec 11, 2025 Retrieved Oct 9, 2026 · CC-BY
Open source ↗
75.8 reasoning
lmarena text 1365.4 eloLMArena / ArenaPublished source fact [variant] text / overallPublished Oct 2, 2026 Retrieved Oct 9, 2026 · CC-BY-4.0
Open source ↗
69.6 preference
otis mock aime 2024 2025 88.9%Epoch AI BenchmarkingEpoch-owned evaluation mean score; scores only, no benchmark questions [variant] highPublished Dec 11, 2025 Retrieved Oct 9, 2026 · CC-BY
Open source ↗
88.9 math
swe bench pro public 16.2%SWE-bench Pro (public)Published steward score [variant] Published Jan 27, 2026 Retrieved Oct 9, 2026 · factual citation
Open source ↗
16.2 coding
swe bench verified 26%SWE-bench VerifiedSWE-bench published model plus agent result; harness retained, not a base model evaluation [variant] mini-SWE-agent; 1.7.0Published Aug 7, 2025 Retrieved Oct 9, 2026 · factual citation
Open source ↗
26.0 coding

Normalization uses fixed absolute 0–100 scales for each unit, independently of other models that have a result on each benchmark. Coverage and evidence breadth still affect the composite; compare the evaluation conditions before reading a small score gap as decisive. “lab-reported” marks the provider's own published figure.

Sources: in and pending

in Reported (5)

  • Aider polyglot · arrived Oct 8, 2026
  • Epoch AI Benchmarking · arrived Oct 8, 2026
  • LMArena / Arena · arrived Oct 8, 2026
  • SWE-bench Verified · arrived Oct 8, 2026
  • SWE-bench Pro (public) · arrived Oct 8, 2026

pending Awaiting (5)

  • ARC Prize · carries 10% of expected weight
  • Humanity’s Last Exam · carries 10% of expected weight
  • Official model cards via models.dev · carries 3% of expected weight
  • LiveBench · carries 10% of expected weight
  • Terminal-Bench · carries 5% of expected weight

The confidence % rises as pending sources publish. Some sources never cover some models — that is why 100% confidence arrives at 80% of expected weight, not at full coverage.