Compare · ModelsLive · 3 picked · head to head

Claude Fable 5 vs Claude Opus 4.8 vs GPT-5.4

Side by side · benchmarks, pricing, and signals you can act on.

Winner summary

Claude Fable 5 wins 11 of 19 shared benchmarks. Leads in agentic · arena · math.

Category leads
agentic·Claude Fable 5arena·Claude Fable 5knowledge·GPT-5.4math·Claude Fable 5coding·Claude Fable 5speed·Claude Fable 5reasoning·GPT-5.4
Hype vs Reality
Claude Fable 5
#12 by perf·no signal
QUIET
Claude Opus 4.8
#47 by perf·no signal
QUIET
GPT-5.4
#61 by perf·no signal
QUIET
Best value
1.6x better value than Claude Opus 4.8
Claude Fable 5
2.5 pts/$
$30.00/M
Claude Opus 4.8
4.1 pts/$
$15.00/M
GPT-5.4
6.7 pts/$
$8.75/M
Vendor risk
Anthropic logo
Anthropic
$380.0B·Tier 1
Medium risk
Anthropic logo
Anthropic
$380.0B·Tier 1
Medium risk
OpenAI logo
OpenAI
$840.0B·Tier 1
Medium risk
Head to head
Claude Fable 5Claude Opus 4.8GPT-5.4
APEX-Agents
Claude Fable 5 leads by +2.5
APEX-Agents · evaluates AI agents on complex, multi-step tasks requiring planning, tool use, and autonomous decision-making in realistic environments.
Claude Fable 5
45.0
Claude Opus 4.8
42.5
GPT-5.4
35.9
Chatbot Arena Elo · Coding
Claude Fable 5 leads by +111.7
Claude Fable 5
1653.9
Claude Opus 4.8
1542.3
GPT-5.4
1411.1
Chatbot Arena Elo · Overall
Claude Fable 5 leads by +29.7
Claude Fable 5
1507.6
Claude Opus 4.8
1477.8
GPT-5.4
1467.7
Chess Puzzles
GPT-5.4 leads by +3.0
Chess Puzzles · tests strategic and tactical reasoning by having models solve chess puzzle positions, evaluating lookahead and pattern recognition abilities.
Claude Fable 5
41.0
Claude Opus 4.8
34.0
GPT-5.4
44.0
FrontierMath-Tier-4-v2-Private
Claude Fable 5 leads by +31.7
Claude Fable 5
87.8
Claude Opus 4.8
56.1
GPT-5.4
49.0
FrontierMath-Tiers-1-3-v2-Private
Claude Fable 5 leads by +7.0
Claude Fable 5
87.0
Claude Opus 4.8
80.0
GPT-5.4
78.6
OTIS Mock AIME 2024-2025
Claude Fable 5 leads by +1.4
OTIS Mock AIME 2024-2025 · simulated American Invitational Mathematics Examination problems testing advanced problem-solving skills.
Claude Fable 5
99.7
Claude Opus 4.8
98.3
GPT-5.4
95.3
SimpleQA Verified
Claude Fable 5 leads by +23.5
SimpleQA Verified · short factual questions with verified answers, measuring factual accuracy and the tendency to hallucinate or provide incorrect information.
Claude Fable 5
68.3
Claude Opus 4.8
39.5
GPT-5.4
44.8
WeirdML
Claude Fable 5 leads by +5.0
WeirdML · tests models on unusual and adversarial machine learning tasks that require creative problem-solving beyond standard patterns.
Claude Fable 5
87.8
Claude Opus 4.8
82.9
GPT-5.4
77.7
Artificial Analysis · Agentic Index
GPT-5.4 leads by +16.6
Artificial Analysis Agentic Index · a composite score measuring how well a model performs in agentic workflows · multi-step tool use, planning, error recovery, and autonomous task completion. Aggregates results from multiple agentic benchmarks including SWE-bench, tool-use tests, and planning evaluations. The canonical single-number metric for "how good is this model as an agent?"
Claude Fable 5
52.8
GPT-5.4
69.4
Artificial Analysis · Coding Index
Claude Fable 5 leads by +19.2
Artificial Analysis Coding Index · a composite score that aggregates performance across multiple coding benchmarks into a single index. Tracks code generation quality, debugging ability, multi-language competence, and real-world software engineering tasks. Used by Artificial Analysis to rank model coding capability in a normalized, comparable format. Useful for developers choosing between models for coding-heavy workloads.
Claude Fable 5
76.5
GPT-5.4
57.3
Artificial Analysis · Quality Index
Claude Fable 5 leads by +2.7
Claude Fable 5
59.9
GPT-5.4
57.2
ARC-AGI
GPT-5.4 leads by +1.2
ARC-AGI · the original Abstraction and Reasoning Corpus, testing whether AI can solve novel visual pattern recognition tasks without memorization.
Claude Opus 4.8
92.5
GPT-5.4
93.7
ARC-AGI-2
GPT-5.4 leads by +1.9
ARC-AGI-2 · the second iteration of the Abstraction and Reasoning Corpus, testing novel pattern recognition and abstract reasoning without prior training data.
Claude Opus 4.8
72.1
GPT-5.4
74.0
FrontierMath-2025-02-28-Private
GPT-5.4 leads by +0.4
FrontierMath (Feb 2025) · original research-level math problems created by mathematicians, testing capabilities at the boundary of current AI mathematical reasoning.
Claude Opus 4.8
47.2
GPT-5.4
47.6
FrontierMath-Tier-4-2025-07-01-Private
Claude Opus 4.8 leads by +4.1
FrontierMath Tier 4 (Jul 2025) · the most challenging tier of frontier mathematics, containing problems that push the absolute limits of AI mathematical reasoning.
Claude Opus 4.8
31.3
GPT-5.4
27.1
GPQA diamond
GPT-5.4 leads by +3.0
Graduate-Level Google-Proof QA (Diamond set) · expert-crafted questions in physics, biology, and chemistry that are difficult even for domain PhDs.
Claude Opus 4.8
88.0
GPT-5.4
91.1
PostTrainBench
Claude Opus 4.8 leads by +17.0
Claude Opus 4.8
37.2
GPT-5.4
20.2
SimpleBench
Claude Fable 5 leads by +20.5
SimpleBench · tests fundamental reasoning capabilities with straightforward problems designed to expose gaps in basic logical and spatial thinking.
Claude Fable 5
78.3
Claude Opus 4.8
57.8
Full benchmark table
BenchmarkClaude Fable 5Claude Opus 4.8GPT-5.4
APEX-Agents
APEX-Agents · evaluates AI agents on complex, multi-step tasks requiring planning, tool use, and autonomous decision-making in realistic environments.
45.042.535.9
Chatbot Arena Elo · Coding
1653.91542.31411.1
Chatbot Arena Elo · Overall
1507.61477.81467.7
Chess Puzzles
Chess Puzzles · tests strategic and tactical reasoning by having models solve chess puzzle positions, evaluating lookahead and pattern recognition abilities.
41.034.044.0
FrontierMath-Tier-4-v2-Private
87.856.149.0
FrontierMath-Tiers-1-3-v2-Private
87.080.078.6
OTIS Mock AIME 2024-2025
OTIS Mock AIME 2024-2025 · simulated American Invitational Mathematics Examination problems testing advanced problem-solving skills.
99.798.395.3
SimpleQA Verified
SimpleQA Verified · short factual questions with verified answers, measuring factual accuracy and the tendency to hallucinate or provide incorrect information.
68.339.544.8
WeirdML
WeirdML · tests models on unusual and adversarial machine learning tasks that require creative problem-solving beyond standard patterns.
87.882.977.7
Artificial Analysis · Agentic Index
Artificial Analysis Agentic Index · a composite score measuring how well a model performs in agentic workflows · multi-step tool use, planning, error recovery, and autonomous task completion. Aggregates results from multiple agentic benchmarks including SWE-bench, tool-use tests, and planning evaluations. The canonical single-number metric for "how good is this model as an agent?"
52.869.4
Artificial Analysis · Coding Index
Artificial Analysis Coding Index · a composite score that aggregates performance across multiple coding benchmarks into a single index. Tracks code generation quality, debugging ability, multi-language competence, and real-world software engineering tasks. Used by Artificial Analysis to rank model coding capability in a normalized, comparable format. Useful for developers choosing between models for coding-heavy workloads.
76.557.3
Artificial Analysis · Quality Index
59.957.2
ARC-AGI
ARC-AGI · the original Abstraction and Reasoning Corpus, testing whether AI can solve novel visual pattern recognition tasks without memorization.
92.593.7
ARC-AGI-2
ARC-AGI-2 · the second iteration of the Abstraction and Reasoning Corpus, testing novel pattern recognition and abstract reasoning without prior training data.
72.174.0
FrontierMath-2025-02-28-Private
FrontierMath (Feb 2025) · original research-level math problems created by mathematicians, testing capabilities at the boundary of current AI mathematical reasoning.
47.247.6
FrontierMath-Tier-4-2025-07-01-Private
FrontierMath Tier 4 (Jul 2025) · the most challenging tier of frontier mathematics, containing problems that push the absolute limits of AI mathematical reasoning.
31.327.1
GPQA diamond
Graduate-Level Google-Proof QA (Diamond set) · expert-crafted questions in physics, biology, and chemistry that are difficult even for domain PhDs.
88.091.1
PostTrainBench
37.220.2
SimpleBench
SimpleBench · tests fundamental reasoning capabilities with straightforward problems designed to expose gaps in basic logical and spatial thinking.
78.357.8
Pricing · per 1M tokens · projected $/mo at 10M tokens
ModelInputOutputContextProjected $/mo
Anthropic logoClaude Fable 5$10.00$50.001.0M tokens (~500 books)$200.00
Anthropic logoClaude Opus 4.8$5.00$25.001.0M tokens (~500 books)$100.00
OpenAI logoGPT-5.4$2.50$15.001.1M tokens (~525 books)$56.25