Claude Fable 5.1 vs Claude Opus 5: Release Comparison

Comparison of the Claude Fable 5.1 and Claude Opus 5 releases: 5 and 5 models respectively, each with different intelligence, performance, and pricing characteristics. Below is a comparison of the key metrics across all 10 models.

  • For intelligence, Claude Fable 5.1 scores highest: Claude Fable 5.1 (Adaptive Reasoning, Max Effort, Default Fallback) at 53, against Claude Opus 5 (Adaptive Reasoning, Max Effort) at 51 for Claude Opus 5.
  • For output speed, Claude Fable 5.1 is fastest: Claude Fable 5.1 (Adaptive Reasoning, Max Effort, Default Fallback) at 66 t/s, against Claude Opus 5 (Adaptive Reasoning, Medium Effort) at 57 t/s for Claude Opus 5.
  • For cost per task, Claude Opus 5 is cheapest: Claude Opus 5 (Adaptive Reasoning, Low Effort) at $1.10, 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 v4.3.2 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

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
Claude Opus 5
Pareto line

Cost per Task (USD, Log Scale)

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

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: AA-Omniscience, GDPval-AA v2.1, AA-Briefcase v1.1, 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

Further details

Input modality
Output modality
Weights
Provider Benchmarks
Claude Fable 5.1 (Adaptive Reasoning, Max Effort, Default Fallback)
Anthropic logoAnthropic
53
56
60
60
58
56
63
$7.63
$7.2
$10.00
$50.00
$0.25
$13,129
78k
47k
188M
66
311.51s
311.51s
319.12s
751.16s
-
1M
Sep 2026
-
Yes

Supports: text and image

Supports: text

Not available
-
Anthropic
Claude Fable 5.1 (Adaptive Reasoning, Xhigh Effort, Default Fallback)
Anthropic logoAnthropic
53
56
58
61
-
57
62
$5.98
$7.2
$10.00
$50.00
$0.25
$9,063
61k
34k
121M
61
164.82s
164.82s
173.02s
621.69s
-
1M
Sep 2026
-
Yes

Supports: text and image

Supports: text

Not available
-
Anthropic
Claude Fable 5.1 (Adaptive Reasoning, High Effort, Default Fallback)
Anthropic logoAnthropic
51
54
56
58
-
54
60
$3.91
$7.2
$10.00
$50.00
$0.25
$5,242
38k
19k
62M
55
26.22s
26.22s
35.26s
431.74s
-
1M
Sep 2026
-
Yes

Supports: text and image

Supports: text

Not available
-
Anthropic
Claude Opus 5 (Adaptive Reasoning, Max Effort)
Anthropic logoAnthropic
51
55
57
57
53
54
61
$5.86
$3.9
$5.00
$25.00
$0.50
$7,275
73k
43k
140M
55
62.61s
62.61s
71.71s
804.00s
-
1M
Jul 2026
-
Yes

Supports: text and image

Supports: text

Not available
-
Amazon BedrockAnthropicGoogle
Claude Opus 5 (Adaptive Reasoning, Xhigh Effort)
Anthropic logoAnthropic
50
54
54
56
53
53
60
$4.88
$3.9
$5.00
$25.00
$0.50
$5,868
61k
35k
111M
54
26.58s
26.58s
35.92s
724.44s
-
1M
Jul 2026
-
Yes

Supports: text and image

Supports: text

Not available
-
AnthropicGoogleAmazon Bedrock
Claude Fable 5.1 (Adaptive Reasoning, Medium Effort, Default Fallback)
Anthropic logoAnthropic
49
51
54
57
-
51
58
$2.98
$7.2
$10.00
$50.00
$0.25
$3,983
28k
12k
44M
55
8.61s
8.61s
17.68s
323.37s
-
1M
Sep 2026
-
Yes

Supports: text and image

Supports: text

Not available
-
Anthropic
Claude Opus 5 (Adaptive Reasoning, High Effort)
Anthropic logoAnthropic
48
51
53
54
52
52
58
$3.61
$3.9
$5.00
$25.00
$0.50
$4,332
46k
25k
81M
55
16.08s
16.08s
25.14s
517.71s
-
1M
Jul 2026
-
Yes

Supports: text and image

Supports: text

Not available
-
AnthropicGoogleAmazon Bedrock
Claude Fable 5.1 (Adaptive Reasoning, Low Effort, Default Fallback)
Anthropic logoAnthropic
47
49
51
53
-
49
55
$2.37
$7.2
$10.00
$50.00
$0.25
$3,158
22k
8k
33M
54
7.28s
7.28s
16.52s
251.70s
-
1M
Sep 2026
-
Yes

Supports: text and image

Supports: text

Not available
-
Anthropic
Claude Opus 5 (Adaptive Reasoning, Medium Effort)
Anthropic logoAnthropic
45
49
51
52
50
47
56
$2.19
$3.9
$5.00
$25.00
$0.50
$2,732
29k
15k
49M
57
5.20s
5.20s
13.99s
314.21s
-
1M
Jul 2026
-
Yes

Supports: text and image

Supports: text

Not available
-
AnthropicAmazon BedrockGoogle
Claude Opus 5 (Adaptive Reasoning, Low Effort)
Anthropic logoAnthropic
39
44
46
48
45
42
50
$1.10
$3.9
$5.00
$25.00
$0.50
$1,561
15k
7k
26M
56
2.94s
2.94s
11.92s
164.81s
-
1M
Jul 2026
-
Yes

Supports: text and image

Supports: text

Not available
-
AnthropicAmazon BedrockGoogle