BenchLeader

Claude Fable 5 vs Claude Opus 4.1

Verdict
  • Claude Fable 5 leads on quality: 70.5 vs 58.2.
  • Claude Fable 5 is stronger in agents & tools, coding, composite, human preference, instruction following, knowledge, long context, multimodal, reasoning.
  • Claude Opus 4.1 (thinking) is stronger in maths.
  • Claude Fable 5 is 1.5× cheaper ($20.00 vs $30.00 per 1M blended).
  • Claude Fable 5 streams 6.3× faster (63 vs 10 tokens per second).
MetricClaude Fable 5Claude Opus 4.1 (thinking)
BenchLeader Index70.558.2
Agents & tools score74.463.6
Coding score70.553.3
Composite score91.857.9
Human preference score71.664.6
Instruction following score62.952.6
Knowledge score71.458.3
Long context score67.864.5
Multimodal score69.756.5
Reasoning score75.965.6
Maths score59.3
Blended price $/M$20.00$30.00
Output speed63 tok/s10 tok/s
Time to first answer102.3 s3.2 s
Context window1M200k
Remote Labor Index16.1%
APEX-Agents45.0%
FrontierCode53.5%
Epoch Capabilities Index163.4
LMArena Text15071450
LMArena Hard Prompts15331480
LMArena Coding15511512
LMArena WebDev1628
LMArena Vision1330
AA Intelligence Index49.722.9
IFBench63.5%55.4%
AA-LCR82.3%76.0%
MMMU-Pro67.9%
AA-Omniscience43.3
Terminal-Bench Hard62.9%34.3%
GPQA Diamond (AA)92.6%80.9%
Humanity's Last Exam (AA)55.5%12.5%
SciCode (AA)61.0%
τ²-Bench Telecom (AA)98.5%71.4%
AIME (Vals)78.2%
LiveCodeBench89.8%66.5%
MMLU-Pro91.5%87.9%
IOI72.3%
LegalBench88.6%
CorpFin71.8%
TaxEval76.9%73.7%
MedQA93.6%
MGSM94.4%
Terminal-Bench 2.1 (Vals)80.5%
SWE-bench (Vals)95.0%
GPQA Diamond (Vals)93.2%76.3%
Vals Index66.0
MCP Atlas83.3%
MultiChallenge57.2%
PRBench Finance53.9%
PRBench Legal52.6%
VISTA48.4%
MultiNRC38.4%
HiL-Bench56.3%
TutorBench50.8%
EQ-Bench 41340
Kagi LLM Benchmark88.8%

Data as of 2026-09-10. Best configuration of each model; every score links to its source on the model pages.

Claude Fable 5 vs Claude Opus 4.1: questions

Is Claude Fable 5 better than Claude Opus 4.1?
Claude Fable 5 leads on quality: 70.5 vs 58.2. The BenchLeader Index combines every independent quality benchmark; Claude Fable 5 is ahead overall as of 2026-09-10, but check the category scores for your use.
Is Claude Fable 5 better than Claude Opus 4.1 for coding?
Claude Fable 5 scores higher in coding (71 vs 53 on the category index, where 50 is average).
Is Claude Fable 5 better than Claude Opus 4.1 for agentic tasks?
Claude Fable 5 scores higher in agentic tasks (74 vs 64 on the category index, where 50 is average).
Which is cheaper, Claude Fable 5 or Claude Opus 4.1?
Claude Fable 5 is cheaper: $20.00 against $30.00 per million tokens, blended at three input tokens per output token.
Which is faster, Claude Fable 5 or Claude Opus 4.1?
Claude Fable 5 streams faster: 63 against 10 output tokens per second.
Which has the larger context window?
Claude Fable 5 accepts more context: 1M against 200k tokens.