Model comparison

Claude Fable 5 vs o3-pro

Claude Fable 5 is the stronger model overall, scoring 66.8 to 42.9 on the Noometry Index.

Last verified . 7 shared benchmarks.

Claude Fable 5 Anthropic

66.8

Rank #5 Confirmed

o3-pro OpenAI

42.9

Rank #105 Confirmed

Summary

  • They share 7 benchmarks with published results for both. Claude Fable 5 scores higher in 4 categories and o3-pro in 1 category; 5 gaps are clear of the uncertainty.
  • The widest gap is in reasoning, where Claude Fable 5 leads 76.8 to 23.8.
  • The biggest single-benchmark swing is ARC-AGI-2: 89.2% for Claude Fable 5 and 4.9% for o3-pro.
  • Claude Fable 5 is cheaper at $10 / $50 per million input/output tokens, against $20 / $80 for o3-pro.
  • Claude Fable 5 accepts more context: 1M tokens versus 200K.

Side by side

Claude Fable 5 and o3-pro specifications
Claude Fable 5o3-pro
ProviderAnthropicOpenAI
Noometry Index66.842.9
Released2026-06-072025-06-10
WeightsProprietaryProprietary
Context window1M200K
Max output128K100K
Input $ / M tokens$10$20
Output $ / M tokens$50$80
Results tracked6212

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Category by category

Coding Claude Fable 5 leads

Claude Fable 5: 70.6 (#4), o3-pro: 55.5 (#24)

Coding benchmarks
BenchmarkClaude Fable 5o3-pro
WeirdML91.9%58.2%
DeepSWE69.9%—
FrontierCode53.5%—
Aider Polyglot—84.9%
LMArena WebDev1625—
FrontierSWE47%—
SciCode61%—
GSO78.4%—
LMArena Coding1519—
MirrorCode63.9%—
ALE-Bench2,041—

Agentic & Tool Use Not comparable

Claude Fable 5: 54.0 (#2), o3-pro: —

Agentic & Tool Use benchmarks
BenchmarkClaude Fable 5o3-pro
APEX-Agents63.6%—
Remote Labor Index16.1%—
τ²-bench Banking39.7%—
PostTrainBench41.8%—
GBAEval74.5%—
GDP.pdf30%—
LMArena Search1230—
Vending-Bench 25,680—

Reasoning Claude Fable 5 leads

Claude Fable 5: 76.8 (#6), o3-pro: 23.8 (#171)

Reasoning benchmarks
BenchmarkClaude Fable 5o3-pro
ARC-AGI-289.2%4.9%
Kagi LLM Benchmark91.4%72.1%
ARC-AGI-198.5%59.3%
DTBench98.4%86.9%
LMCA61.1%38.5%
Epoch Capabilities Index162.06147.42
SimpleBench81.9%—
NYT Connections (extended)92.7%—
CritPt28.6%—
Chess Puzzles41%—
EnigmaEval39.3%—
EBR-Bench39.5%—
LMArena Hard Prompts1508—
Mystery Game Puzzles52%—
Surface Evolver Bench95%—
Bench to the Future 30.13—

Math Not comparable

Claude Fable 5: 88.5 (#5), o3-pro: —

Math benchmarks
BenchmarkClaude Fable 5o3-pro
FrontierMath (Tiers 1-3)87%—
FrontierMath Tier 490.2%—
OTIS Mock AIME 2024-2025100%—
ProofBench95%—
LMArena Math1519—
FrontierMath Erdős0%—

Knowledge Claude Fable 5 leads

Claude Fable 5: 62.2 (#25), o3-pro: 29.5 (#238)

Knowledge benchmarks
BenchmarkClaude Fable 5o3-pro
GPQA Diamond85.9%—
SimpleQA Verified70.7%—
Confabulations—14.2%
Vectara Hallucination Rate—23.3%
LMArena Expert1534—

Multimodal Not comparable

Claude Fable 5: 45.3 (#17), o3-pro: —

Multimodal benchmarks
BenchmarkClaude Fable 5o3-pro
LMArena Vision1324—
Blueprint-Bench 238.6%—
Furniture Assembly35.8%—
LMArena Document1496—

Multilingual Not comparable

Claude Fable 5: 57.3 (#9), o3-pro: —

Multilingual benchmarks
BenchmarkClaude Fable 5o3-pro
LMArena Non-English1481—
LMArena Chinese1543—
LMArena French1505—
LMArena German1486—
LMArena Japanese1506—
LMArena Korean1488—
LMArena Russian1504—
LMArena Spanish1498—

Instruction Following Not comparable

Claude Fable 5: 78.6 (#8), o3-pro: —

Instruction Following benchmarks
BenchmarkClaude Fable 5o3-pro
LMArena Instruction Following1502—

Long Context o3-pro leads

Claude Fable 5: 46.3 (#23), o3-pro: 72.2 (#1)

Long Context benchmarks
BenchmarkClaude Fable 5o3-pro
Fiction.LiveBench—97.2%
LMArena Longer Query1509—

Writing & Preference Claude Fable 5 leads

Claude Fable 5: 75.9 (#5), o3-pro: 57.1 (#133)

Writing & Preference benchmarks
BenchmarkClaude Fable 5o3-pro
LMArena Text1491—
LMArena Creative Writing1494—
Short-Story Creative Writing—84.4%
EQ-Bench Creative Writing1943—
EQ-Bench 41340—
LMArena Multi-Turn1504—

Frequently asked questions

Is Claude Fable 5 better than o3-pro?

Claude Fable 5 is the stronger model overall, scoring 66.8 to 42.9 on the Noometry Index.

Which is cheaper, Claude Fable 5 or o3-pro?

Claude Fable 5 is cheaper. It lists at $10 per million input tokens and $50 per million output tokens; o3-pro lists at $20 and $80.

Is Claude Fable 5 or o3-pro better for coding?

Claude Fable 5 scores higher on coding benchmarks: 70.6 versus 55.5 in the Noometry coding category.

Which has the bigger context window?

Claude Fable 5 does, with 1M tokens against 200K.

How many benchmarks do Claude Fable 5 and o3-pro share?

7 benchmarks have published results for both models. Claude Fable 5 has 62 scored results on Noometry and o3-pro has 12.

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