Claude Fable 5.1 vs gpt-oss-120b: Release Comparison

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

Comparison of the Claude Fable 5.1 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 Fable 5.1 scores highest: Claude Fable 5.1 (Adaptive Reasoning, Max Effort, Default Fallback) at 53, against gpt-oss-120b (high) at 12 for gpt-oss-120b.
For output speed, gpt-oss-120b is fastest: gpt-oss-120b (high) at 205 t/s, against Claude Fable 5.1 (Adaptive Reasoning, Max Effort, Default Fallback) at 65 t/s for Claude Fable 5.1.
For cost per task, gpt-oss-120b is cheapest: gpt-oss-120b (high) at $0.11, against Claude Fable 5.1 (Adaptive Reasoning, Low Effort, Default Fallback) at $2.37 for Claude Fable 5.1.

Releases compared

Intelligence

Artificial Analysis Intelligence Index

Artificial Analysis Intelligence Index v4.3 incorporates 10 evaluations: AA-Briefcase, GDPval-AA v2, AutomationBench-AA, Terminal-Bench 4.0, SciCode, Humanity's Last Exam, GDP.pdf, CritPt, AA-Omniscience, AA-LCR v1.1

Estimate (independent evaluation forthcoming)

Artificial Analysis Intelligence Index v4.3 includes: AA-Briefcase, GDPval-AA v2, 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 Fable 5.1

Pareto line

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

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 (e.g. OpenAI for o1) or the median across providers where a first-party API is not available (e.g. Meta's Llama models).

Capability Scores

Capability Indices

Measures the performance of models on specific capabilities and industries

Finance & Accounting Index

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

Strategy & Ops Index

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

Legal Index

Incorporates 7 evaluations: AA-Omniscience, GDPval-AA v2, AA-Briefcase, 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, AA-Briefcase, 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, AA-Briefcase, Terminal-Bench 4.0 · Higher is better

Economics Index

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

Further details


																												Input modality	Output modality	Weights			Provider Benchmarks
Claude Fable 5.1 (Adaptive Reasoning, Max Effort, Default Fallback)	Anthropic	53	57	60	61	58	57	63	$7.63	$7.2	$10.00	$50.00	$0.25	$13,129	78k	47k	188M	65	210.79s	210.79s	218.47s	761.08s	-	1M	Sep 2026	-	Yes	Supports: text and image	Supports: text	Not available	-		View
Claude Fable 5.1 (Adaptive Reasoning, Xhigh Effort, Default Fallback)	Anthropic	53	56	58	61	-	57	62	$5.98	$7.2	$10.00	$50.00	$0.25	$9,063	61k	34k	121M	58	91.63s	91.63s	100.23s	698.65s	-	1M	Sep 2026	-	Yes	Supports: text and image	Supports: text	Not available	-		View
Claude Fable 5.1 (Adaptive Reasoning, High Effort, Default Fallback)	Anthropic	51	54	56	58	-	55	60	$3.91	$7.2	$10.00	$50.00	$0.25	$5,242	38k	19k	62M	51	12.45s	12.45s	22.32s	469.10s	-	1M	Sep 2026	-	Yes	Supports: text and image	Supports: text	Not available	-		View
Claude Fable 5.1 (Adaptive Reasoning, Medium Effort, Default Fallback)	Anthropic	49	52	54	57	-	52	58	$2.98	$7.2	$10.00	$50.00	$0.25	$3,983	28k	12k	44M	51	6.49s	6.49s	16.33s	337.28s	-	1M	Sep 2026	-	Yes	Supports: text and image	Supports: text	Not available	-		View
Claude Fable 5.1 (Adaptive Reasoning, Low Effort, Default Fallback)	Anthropic	47	49	52	54	-	49	55	$2.37	$7.2	$10.00	$50.00	$0.25	$3,158	22k	8k	33M	50	5.23s	5.23s	15.15s	280.39s	-	1M	Sep 2026	-	Yes	Supports: text and image	Supports: text	Not available	-		View
gpt-oss-120b (high)	OpenAI	12	13	9	12	12	16	19	$0.11	$0.2	$0.15	$0.595	$0.125	$122	27k	15k	84M	205	0.84s	10.58s	13.01s	130.69s	117B 5.1B active at inference time	131k	Aug 2025	May 2024	Yes	Supports: text	Supports: text	🤗	Apache 2.0	+14	View
gpt-oss-120b (low)	OpenAI	10	-	-	-	-	-	-	-	$0.2	$0.15	$0.545	$0.15	-	-	-	-	202	0.84s	10.71s	13.18s	-	117B 5.1B active at inference time	131k	Aug 2025	May 2025	Yes	Supports: text	Supports: text	🤗	Apache 2.0	+14	View

Claude Fable 5.1 vs gpt-oss-120b: Release Comparison

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 Indices

Further details