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Claude Opus 4vsgpt-oss-20b

Claude Opus 4 leads 2 of 3 shared benchmarks. Claude Opus 4 has the larger context window (200K tokens).

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

Shared benchmarks
2 – 1
Claude Opus 4 leads
Cheaper per token
list price, input + output
Larger context
Claude Opus 4
200K tokens
Provider uptime (30d)
100% · 94.2446%
Anthropic · OpenAI
Claude Opus 4
Anthropic · released 2025-05-22
textvision
Context
200K
Max out
32K
Input /1M
$15
Output /1M
$75
Cached /1M
$1.5
Scores
6 · 5 core
gpt-oss-20b
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 4gpt-oss-20bΔEdge
Reported by both · 3
SWE-bench Verified72.5% 60.7% +11.8 ptClaude Opus 4
GPQA Diamond76.3% epoch71.5% +4.8 ptClaude Opus 4
OTIS Mock AIME 2024-2025 (Epoch AI run)64.4% epoch65.3% epoch-0.9 ptgpt-oss-20b
Only Claude Opus 4 reports · 3
AIME 2024 (no extended thinking)33.9% not reported
SWE-bench Verified (Epoch AI run)70.7% epochnot reported
Terminal-bench43.2% not reported
Only gpt-oss-20b reports · 2
AIME 2025not reported89.2% matharena
LMArena Elonot reported1287.3
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 minus gpt-oss-20b 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 4gpt-oss-20bEdge
Context window200K tokens131K tokensClaude Opus 4
Max output32K tokens131K tokensgpt-oss-20b
Input price / 1M$15
Output price / 1M$75
Cached input / 1M$1.5
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
$90
Modalitiestext · visiontextClaude Opus 4
Released2025-05-222025-08-05
Cited benchmark scores66
Reliability

Provider status

All providers
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Public benchmarks are a starting point. Run Claude Opus 4 and gpt-oss-20b on your own prompts with Respan evals, or route to either through one gateway key with automatic failover.