Claude Opus 5.5 vs gpt-oss-120b: Release Comparison

Name: Intelligence
Creator: Artificial Analysis
License: https://artificialanalysis.ai/docs/legal/Terms-of-Use.pdf

Comparison of the Claude Opus 5.5 and gpt-oss-120b releases: 5 and 2 models respectively, each with different intelligence, performance, and pricing characteristics. Below is a comparison of the key metrics across all 7 models.

For intelligence, Claude Opus 5.5 scores highest: Claude Opus 5.5 (Max, Default Fallback) at 58, against gpt-oss-120b (High) at 12 for gpt-oss-120b.
For output speed, gpt-oss-120b is fastest: gpt-oss-120b (Low) at 244 t/s, against Claude Opus 5.5 (Max, Default Fallback) at 96 t/s for Claude Opus 5.5.
For cost per task, gpt-oss-120b is cheapest: gpt-oss-120b (High) at $0.11, against Claude Opus 5.5 (Low, Default Fallback) at $0.55 for Claude Opus 5.5.

Model Playground

Releases compared


	Claude Opus 5.5 (max with fallback)	Claude Opus 5.5 (xhigh with fallback)	Claude Opus 5.5 (high with fallback)	Claude Opus 5.5 (medium with fallback)	Claude Opus 5.5 (low with fallback)	gpt-oss-120b (high)	gpt-oss-120b (low)
Intelligence Index	58	56	54	51	42	12	10*
Finance & Accounting	61	58	56	54	46	12	--
Strategy & Ops	64	62	59	57	48	8	--
Legal	63	61	59	57	52	11	--
Healthcare & Medical	61	--	--	--	--	11	--
Engineering	60	59	56	54	45	15	--
Economics	66	63	61	60	53	18	--
AA-Briefcase v1.1	1807	1766	1690	1627	1279	0	--
GDPval-AA v2.1	1866	1836	1705	1584	1234	608	172
AutomationBench-AA	69.5%	65.0%	63.2%	61.2%	52.9%	0.2%	--
Terminal-Bench 4.0	59.6%	59.6%	56.6%	52.5%	31.3%	0.0%	--
SciCode	66.9%	65.0%	60.4%	59.3%	58.6%	34.0%	--
Humanity's Last Exam	61.4%	57.5%	55.6%	54.7%	48.3%	19.6%	5.9%
GDP.pdf	26.2%	26.6%	28.8%	25.6%	25.6%	4.0%	--
CritPt	31.7%	31.7%	30.9%	27.7%	17.7%	1.1%	0.0%
AA-Omniscience	46	43	41	40	39	−49	−54
AA-LCR v1.1	84.7%	84.7%	82.7%	84.3%	80.7%	52.0%	46.0%

Cost per TaskUSD	$5.98	$3.46	$1.82	$1.34	$0.55	$0.11	--
Input PriceUSD/1M Tokens	$4.00	$4.00	$4.00	$4.00	$4.00	$0.15	$0.15
Output PriceUSD/1M Tokens	$20.00	$20.00	$20.00	$20.00	$20.00	$0.59	$0.50
Cache Hit PriceUSD/1M Tokens	$0.20	$0.20	$0.20	$0.20	$0.20	$0.10	$0.15
Cache Write PriceUSD/1M Tokens	$5.00	$5.00	$5.00	$5.00	$5.00	--	--

Output SpeedTokens/s	96	81	82	79	80	242	244
Time to First Tokens	748.61	154.80	45.11	23.85	12.35	0.83	0.82
Time to First Answer Tokens	748.61	154.80	45.11	23.85	12.35	9.09	9.03
End-to-End Response Times	753.84	160.94	51.20	30.19	18.60	11.15	11.08
Time per Tasks	780.94	496.52	276.27	202.93	80.85	108.75	--

Context Window	1M	1M	1M	1M	1M	131k	131k
Creator	Anthropic	Anthropic	Anthropic	Anthropic	Anthropic	OpenAI	OpenAI
License	Proprietary	Proprietary	Proprietary	Proprietary	Proprietary	Open	Open
Input Modality	Supports: text and image	Supports: text and image	Supports: text and image	Supports: text and image	Supports: text and image	Supports: text	Supports: text
Output Modality	Supports: text	Supports: text	Supports: text	Supports: text	Supports: text	Supports: text	Supports: text
Providers						+13	+13

* Estimated

Intelligence

Artificial Analysis Intelligence Index · Higher is better

Speed

Output tokens per second · Higher is better

Cost per Task

Weighted average cost (USD) per Intelligence Index task · Lower is better

Intelligence

Artificial Analysis Intelligence Index

Artificial Analysis Intelligence Index v4.3.2 incorporates 10 evaluations: AA-Briefcase v1.1, GDPval-AA v2.1, AutomationBench-AA, Terminal-Bench 4.0, SciCode, Humanity's Last Exam, GDP.pdf, CritPt, AA-Omniscience, AA-LCR v1.1

No publicly available API

Estimate (independent evaluation forthcoming)

Artificial Analysis Intelligence Index v4.3.2 includes: AA-Briefcase v1.1, GDPval-AA v2.1, AutomationBench-AA, Terminal-Bench 4.0, SciCode, Humanity's Last Exam, GDP.pdf, CritPt, AA-Omniscience, AA-LCR v1.1. See Intelligence Index methodology for further details, including a breakdown of each evaluation and how we run them.

Intelligence Index vs. Cost per Intelligence Index Task

Artificial Analysis Intelligence Index · Weighted average cost (USD) per Artificial Analysis Intelligence Index task

Most attractive quadrant

Claude Opus 5.5

Pareto line

AA-Briefcase v1.1

GDPval-AA v2.1

Cost per Task (USD, Log Scale)

Weighted average cost per Intelligence Index task. Each evaluation’s cost is calculated from input, cache hit, cache write, reasoning, and answer token prices, divided by task count, and weighted by its Intelligence Index weight.

Cost

Cost per Intelligence Index Task

Weighted average cost (USD) per Artificial Analysis Intelligence Index task, segmented by token type. Lower is better

No publicly available API

Speed & Latency

Output Speed

Output tokens per second · Higher is better

Tokens per second received while the model is generating tokens (ie. after first chunk has been received from the API for models which support streaming).

Figures represent performance of the model's first-party API or the median across providers where a first-party API is not available.

Capability Scores

Capability Indexes

Measures the performance of models on specific capabilities and industries

Finance & Accounting Index

Incorporates 7 evaluations: AA-Omniscience, GDPval-AA v2.1, AA-Briefcase v1.1, Humanity's Last Exam, AutomationBench-AA, AA-LCR v1.1, GDP.pdf · Higher is better

Strategy & Ops Index

Incorporates 6 evaluations: GDPval-AA v2.1, AA-Briefcase v1.1, AA-Omniscience, AutomationBench-AA, AA-LCR v1.1, GDP.pdf · Higher is better

Legal Index

Incorporates 7 evaluations: AA-Omniscience, GDPval-AA v2.1, AA-Briefcase v1.1, Humanity's Last Exam, AA-LCR v1.1, GDP.pdf, AutomationBench-AA · Higher is better

Healthcare & Medical Index

Incorporates 6 evaluations: AA-Omniscience, GDPval-AA v2.1, AA-Briefcase v1.1, MLCR-AA, Humanity's Last Exam, AutomationBench-AA · Higher is better

Engineering Index

Incorporates 6 evaluations: AA-Omniscience, Humanity's Last Exam, CritPt, GDPval-AA v2.1, AA-Briefcase v1.1, Terminal-Bench 4.0 · Higher is better

Economics Index

Incorporates 5 evaluations: AA-Omniscience, Humanity's Last Exam, GDPval-AA v2.1, AA-Briefcase v1.1, AA-LCR v1.1 · Higher is better

Claude Opus 5.5 vs gpt-oss-120b: Release Comparison

Intelligence

Speed

Cost per Task

Intelligence

Artificial Analysis Intelligence Index

Artificial Analysis Intelligence Index

Intelligence Index vs. Cost per Intelligence Index Task

Cost per Intelligence Index Task

Artificial Analysis Intelligence Index

Cost

Cost per Intelligence Index Task

Cost per Intelligence Index Task

Speed & Latency

Output Speed

Output Speed

Model Performance Representation

Capability Scores

Capability Indexes