Noometry

Model comparison

Claude Fable 5.1 vs Reka Flash 3

Claude Fable 5.1 has enough public results to be ranked (#2); Reka Flash 3 does not yet, so treat this comparison as directional.

Last verified . 1 shared benchmarks.

Claude Fable 5.1 Anthropic

68.5

Rank #2 Confirmed

Reka Flash 3 Reka

36.4

Unranked Sparse

Summary

  • They share 1 benchmark with published results for both. Claude Fable 5.1 scores higher in 2 categories and Reka Flash 3 in 0 categories; 2 gaps are clear of the uncertainty.
  • The widest gap is in writing & preference, where Claude Fable 5.1 leads 79.3 to 43.8.
  • Reka Flash 3 is cheaper at $0.10 / $0.20 per million input/output tokens, against $10 / $50 for Claude Fable 5.1.
  • Claude Fable 5.1 accepts more context: 1M tokens versus 66K.
  • Reka Flash 3 has downloadable open weights; the other is API-only.

Side by side

Claude Fable 5.1Reka Flash 3
ProviderAnthropicReka
Noometry Index68.536.4
Released2026-09-012025-03-10
WeightsProprietaryOpen
Context window1M66K
Max output128K59K
Input $ / M tokens$10$0.10
Output $ / M tokens$50$0.20
Results tracked502

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Category by category

Coding Not comparable

Claude Fable 5.1: 70.5 (#2), Reka Flash 3: —

BenchmarkClaude Fable 5.1Reka Flash 3
FrontierCode50.9%—
CursorBench51.8%—
LMArena WebDev1753—
FrontierSWE56.3%—
SciCode63.1%—
WeirdML92.9%—
LMArena Coding1523—
MirrorCode73.3%—
ALE-Bench2,143—

Agentic & Tool Use Claude Fable 5.1 leads

Claude Fable 5.1: 50.8 (#5), Reka Flash 3: 30.1

BenchmarkClaude Fable 5.1Reka Flash 3
APEX-Agents68.6%—
Remote Labor Index17.9%—
BALROG—29.2%
GDP.pdf29.6%—
Vending-Bench 25,422—

Reasoning Not comparable

Claude Fable 5.1: 76.7 (#5), Reka Flash 3: —

BenchmarkClaude Fable 5.1Reka Flash 3
ARC-AGI-290%—
NYT Connections (extended)90%—
ARC-AGI-197.5%—
CritPt31.1%—
Chess Puzzles47%—
EBR-Bench57.1%—
LMArena Hard Prompts1526—
Mystery Game Puzzles58%—
DTBench97.6%—
LMCA65.5%—
Epoch Capabilities Index165—

Math Not comparable

Claude Fable 5.1: 89.5 (#3), Reka Flash 3: —

BenchmarkClaude Fable 5.1Reka Flash 3
FrontierMath (Tiers 1-3)90.2%—
FrontierMath Tier 487.8%—
OTIS Mock AIME 2024-2025100%—
ProofBench100%—
LMArena Math1519—
FrontierMath Erdős0%—

Knowledge Not comparable

Claude Fable 5.1: 69.3 (#5), Reka Flash 3: —

BenchmarkClaude Fable 5.1Reka Flash 3
Humanity's Last Exam46.5%—
SimpleQA Verified70.8%—
LMArena Expert1528—

Multimodal Not comparable

Claude Fable 5.1: 54.1 (#4), Reka Flash 3: —

BenchmarkClaude Fable 5.1Reka Flash 3
LMArena Vision1319—
Blueprint-Bench 241.9%—
Furniture Assembly70%—
LMArena Document1513—

Multilingual Not comparable

Claude Fable 5.1: 59.5 (#2), Reka Flash 3: —

BenchmarkClaude Fable 5.1Reka Flash 3
LMArena Non-English1509—
LMArena Chinese1589—
LMArena French1532—
LMArena German1495—
LMArena Japanese1565—
LMArena Russian1525—
LMArena Spanish1503—

Instruction Following Not comparable

Claude Fable 5.1: 79.3 (#6), Reka Flash 3: —

BenchmarkClaude Fable 5.1Reka Flash 3
LMArena Instruction Following1515—

Long Context Not comparable

Claude Fable 5.1: 46.8 (#19), Reka Flash 3: —

BenchmarkClaude Fable 5.1Reka Flash 3
LMArena Longer Query1524—

Writing & Preference Claude Fable 5.1 leads

Claude Fable 5.1: 79.3 (#1), Reka Flash 3: 43.8

BenchmarkClaude Fable 5.1Reka Flash 3
EQ-Bench Creative Writing21621228
LMArena Text1511—
LMArena Creative Writing1507—
LMArena Multi-Turn1492—

Frequently asked questions

Is Claude Fable 5.1 better than Reka Flash 3?

Claude Fable 5.1 has enough public results to be ranked (#2); Reka Flash 3 does not yet, so treat this comparison as directional.

Which is cheaper, Claude Fable 5.1 or Reka Flash 3?

Reka Flash 3 is cheaper. It lists at $0.10 per million input tokens and $0.20 per million output tokens; Claude Fable 5.1 lists at $10 and $50.

Which has the bigger context window?

Claude Fable 5.1 does, with 1M tokens against 66K.

How many benchmarks do Claude Fable 5.1 and Reka Flash 3 share?

1 benchmark has published results for both models. Claude Fable 5.1 has 50 scored results on Noometry and Reka Flash 3 has 2.

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