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Claude Opus 4.8vsgpt-oss-120b

Claude Opus 4.8 leads 4 of 4 shared benchmarks. Claude Opus 4.8 has the larger context window (1M tokens).

Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.

Shared benchmarks
4 – 0
Claude Opus 4.8 leads
Cheaper per token
list price, input + output
Larger context
Claude Opus 4.8
1M tokens
Provider uptime (30d)
100% · 94.2446%
Anthropic · OpenAI
Claude Opus 4.8
Anthropic · released 2026-05-28
textvision
Context
1M
Max out
128K
Input /1M
$5
Output /1M
$25
Cached /1M
$0.5
Scores
17 · 13 core
gpt-oss-120b
OpenAI · released 2025-08-05
text
Context
131K
Max out
131K
Input /1M
Output /1M
Cached /1M
Scores
6 · 5 core
Quality

Benchmark matrix

BenchmarkClaude Opus 4.8gpt-oss-120bΔEdge
Reported by both · 4
SWE-bench Verified88.6% 62.4% +26.2 ptClaude Opus 4.8
GPQA Diamond93.6% 80.1% +13.5 ptClaude Opus 4.8
LMArena Elo1452.7 1365.9 +86.8Claude Opus 4.8
OTIS Mock AIME 2024-2025 (Epoch AI run)98.3% epoch88.9% epoch+9.4 ptClaude Opus 4.8
Only Claude Opus 4.8 reports · 12
AIME 2026100% matharenanot reported
Humanity's Last Exam (no tools)49.8% not reported
BrowseComp84.3% not reported
FrontierMath Tier 4 v2 (Epoch AI run)56.1% epochnot reported
FrontierMath Tiers 1-3 v2 (Epoch AI run)80% epochnot reported
Humanity's Last Exam (with tools)57.9% not reported
OSWorld-Verified83.4% not reported
SimpleQA Verified53% epochnot reported
SWE-bench Multilingual84.4% not reported
SWE-bench Multimodal38.4% not reported
SWE-Bench Pro69.2% not reported
Terminal-Bench 2.174.6% not reported
Only gpt-oss-120b reports · 1
AIME 2025not reported90% matharena
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is Claude Opus 4.8 minus gpt-oss-120b in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing

Side by side

SpecClaude Opus 4.8gpt-oss-120bEdge
Context window1M tokens131K tokensClaude Opus 4.8
Max output128K tokens131K tokensgpt-oss-120b
Input price / 1M$5
Output price / 1M$25
Cached input / 1M$0.5
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
$30
Modalitiestext · visiontextClaude Opus 4.8
Released2026-05-282025-08-05
Cited benchmark scores176
Reliability

Provider status

All providers
More matchups

Claude Opus 4.8 vs …

More matchups

gpt-oss-120b vs …

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