Model comparison

Claude Fable 5.1 vs Grok 4.6

Claude Fable 5.1 is the stronger model overall, scoring 69.0 to 56.9 on the Noometry Index. Grok 4.6 costs 6.7× less per token, which makes it the better buy when Claude Fable 5.1's lead doesn't matter for your workload.

Last verified . 46 shared benchmarks.

Claude Fable 5.1 Anthropic

69.0

Rank #2 Confirmed

Grok 4.6 xAI

56.9

Rank #21 Confirmed

Summary

  • They share 46 benchmarks with published results for both. Claude Fable 5.1 scores higher in 10 categories and Grok 4.6 in 0 categories; 10 gaps are clear of the uncertainty.
  • The widest gap is in math, where Claude Fable 5.1 leads 89.6 to 67.0.
  • The biggest single-benchmark swing is FrontierMath Tier 4: 87.8% for Claude Fable 5.1 and 31.7% for Grok 4.6.
  • Grok 4.6 is cheaper at $2 / $6 per million input/output tokens, against $10 / $50 for Claude Fable 5.1.
  • Claude Fable 5.1 accepts more context: 1M tokens versus 500K.

Side by side

Claude Fable 5.1 and Grok 4.6 specifications
Claude Fable 5.1Grok 4.6
ProviderAnthropicxAI
Noometry Index69.056.9
Released2026-09-012026-08-12
WeightsProprietaryProprietary
Context window1M500K
Max output128K500K
Input $ / M tokens$10$2
Output $ / M tokens$50$6
Results tracked5249

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Category by category

Coding Claude Fable 5.1 leads

Claude Fable 5.1: 74.7 (#1), Grok 4.6: 58.5 (#16)

Coding benchmarks
BenchmarkClaude Fable 5.1Grok 4.6
FrontierCode50.9%48%
CursorBench51.8%41.4%
LMArena WebDev17441617
FrontierSWE56.3%25.3%
SciCode63.1%56.5%
WeirdML92.9%67.3%
LMArena Coding15281465
ALE-Bench2,1431,508
DeepSWE—67.5%
GSO88.2%—
MirrorCode73.3%—

Agentic & Tool Use Claude Fable 5.1 leads

Claude Fable 5.1: 50.7 (#5), Grok 4.6: 39.4 (#27)

Agentic & Tool Use benchmarks
BenchmarkClaude Fable 5.1Grok 4.6
APEX-Agents68.6%65.3%
GDP.pdf29.6%17.2%
Vending-Bench 25,4229,047
Remote Labor Index17.9%—

Reasoning Claude Fable 5.1 leads

Claude Fable 5.1: 76.7 (#7), Grok 4.6: 61.4 (#20)

Reasoning benchmarks
BenchmarkClaude Fable 5.1Grok 4.6
ARC-AGI-290%67.1%
NYT Connections (extended)90%80%
ARC-AGI-197.5%87.5%
CritPt31.1%19.7%
Chess Puzzles47%40%
EBR-Bench57.1%30.5%
LMArena Hard Prompts15261447
Mystery Game Puzzles58%34%
DTBench97.6%97.3%
LMCA65.5%48.5%
Epoch Capabilities Index164.7156.44
SimpleBench—75.9%

Math Claude Fable 5.1 leads

Claude Fable 5.1: 89.6 (#4), Grok 4.6: 67.0 (#24)

Math benchmarks
BenchmarkClaude Fable 5.1Grok 4.6
FrontierMath (Tiers 1-3)90.2%66%
FrontierMath Tier 487.8%31.7%
OTIS Mock AIME 2024-2025100%99.2%
ProofBench100%51%
LMArena Math15251423
FrontierMath Erdős0%—

Knowledge Claude Fable 5.1 leads

Claude Fable 5.1: 69.6 (#6), Grok 4.6: 63.3 (#20)

Knowledge benchmarks
BenchmarkClaude Fable 5.1Grok 4.6
SimpleQA Verified70.8%49.3%
LMArena Expert15351467
GPQA Diamond—94%
Humanity's Last Exam46.5%—

Multimodal Claude Fable 5.1 leads

Claude Fable 5.1: 53.9 (#4), Grok 4.6: 43.6 (#23)

Multimodal benchmarks
BenchmarkClaude Fable 5.1Grok 4.6
LMArena Vision13181263
Blueprint-Bench 241.9%33.2%
Furniture Assembly70%40%
LMArena Document15131452

Multilingual Claude Fable 5.1 leads

Claude Fable 5.1: 59.1 (#3), Grok 4.6: 53.0 (#74)

Multilingual benchmarks
BenchmarkClaude Fable 5.1Grok 4.6
LMArena Non-English15071420
LMArena Chinese15861480
LMArena French15251461
LMArena German15001431
LMArena Japanese15431376
LMArena Korean15341397
LMArena Russian15211422
LMArena Spanish15161404

Instruction Following Claude Fable 5.1 leads

Claude Fable 5.1: 79.2 (#6), Grok 4.6: 75.4 (#63)

Instruction Following benchmarks
BenchmarkClaude Fable 5.1Grok 4.6
LMArena Instruction Following15171431

Long Context Claude Fable 5.1 leads

Claude Fable 5.1: 46.7 (#20), Grok 4.6: 44.5 (#66)

Long Context benchmarks
BenchmarkClaude Fable 5.1Grok 4.6
LMArena Longer Query15221454

Writing & Preference Claude Fable 5.1 leads

Claude Fable 5.1: 79.2 (#2), Grok 4.6: 62.3 (#80)

Writing & Preference benchmarks
BenchmarkClaude Fable 5.1Grok 4.6
LMArena Text15101428
LMArena Creative Writing15071428
LMArena Multi-Turn14921425
EQ-Bench Creative Writing2162—

Frequently asked questions

Is Claude Fable 5.1 better than Grok 4.6?

Claude Fable 5.1 is the stronger model overall, scoring 69.0 to 56.9 on the Noometry Index. Grok 4.6 costs 6.7× less per token, which makes it the better buy when Claude Fable 5.1's lead doesn't matter for your workload.

Which is cheaper, Claude Fable 5.1 or Grok 4.6?

Grok 4.6 is cheaper. It lists at $2 per million input tokens and $6 per million output tokens; Claude Fable 5.1 lists at $10 and $50.

Is Claude Fable 5.1 or Grok 4.6 better for coding?

Claude Fable 5.1 scores higher on coding benchmarks: 74.7 versus 58.5 in the Noometry coding category.

Which has the bigger context window?

Claude Fable 5.1 does, with 1M tokens against 500K.

How many benchmarks do Claude Fable 5.1 and Grok 4.6 share?

46 benchmarks have published results for both models. Claude Fable 5.1 has 52 scored results on Noometry and Grok 4.6 has 49.

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