Noometry

Model comparison

C4ai Aya Expanse 8b vs Grok 4.5

Grok 4.5 is the stronger model overall, scoring 55.0 to 34.9 on the Noometry Index.

Last verified . 14 shared benchmarks.

C4ai Aya Expanse 8b Cohere

34.9

Rank #229 Confirmed

Grok 4.5 xAI

55.0

Rank #25 Confirmed

Summary

  • They share 14 benchmarks with published results for both. C4ai Aya Expanse 8b scores higher in 0 categories and Grok 4.5 in 8 categories; 8 gaps are clear of the uncertainty.
  • The widest gap is in reasoning, where Grok 4.5 leads 56.1 to 22.4.
  • C4ai Aya Expanse 8b has downloadable open weights; the other is API-only.

Side by side

C4ai Aya Expanse 8bGrok 4.5
ProviderCoherexAI
Noometry Index34.955.0
Released—2026-07-08
WeightsOpenProprietary
Context window—500K
Max output—500K
Input $ / M tokens—$2
Output $ / M tokens—$6
Results tracked1552

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Category by category

Coding Grok 4.5 leads

C4ai Aya Expanse 8b: 33.8 (#252), Grok 4.5: 52.2 (#35)

BenchmarkC4ai Aya Expanse 8bGrok 4.5
LMArena Coding11601474
DeepSWE—53.8%
FrontierCode—42.4%
LMArena WebDev—1553
SciCode—54.1%
WeirdML—46.4%
ALE-Bench—1,309

Agentic & Tool Use Not comparable

C4ai Aya Expanse 8b: —, Grok 4.5: 44.4 (#17)

BenchmarkC4ai Aya Expanse 8bGrok 4.5
APEX-Agents—56.2%
τ²-bench Banking—47.9%
PostTrainBench—23.4%
GBAEval—65.4%
GDP.pdf—14%
LMArena Search—1213
Vending-Bench 2—3,887

Reasoning Grok 4.5 leads

C4ai Aya Expanse 8b: 22.4 (#197), Grok 4.5: 56.1 (#25)

BenchmarkC4ai Aya Expanse 8bGrok 4.5
LMArena Hard Prompts11561462
ARC-AGI-2—52.6%
SimpleBench—70%
Kagi LLM Benchmark—83.5%
NYT Connections (extended)—79.9%
ARC-AGI-1—87.2%
CritPt—15.4%
Chess Puzzles—36%
DTBench—96.5%
LMCA—45.2%
Surface Evolver Bench—74.4%
Epoch Capabilities Index—153.92

Math Grok 4.5 leads

C4ai Aya Expanse 8b: 33.3 (#203), Grok 4.5: 60.9 (#35)

BenchmarkC4ai Aya Expanse 8bGrok 4.5
LMArena Math11681459
FrontierMath (Tiers 1-3)—57.2%
FrontierMath Tier 4—24.4%
OTIS Mock AIME 2024-2025—97.8%
ProofBench—31%

Knowledge Grok 4.5 leads

C4ai Aya Expanse 8b: 33.6 (#201), Grok 4.5: 62.3 (#24)

BenchmarkC4ai Aya Expanse 8bGrok 4.5
LMArena Expert11531466
GPQA Diamond—93.4%
SimpleQA Verified—48.3%
Vectara Hallucination Rate9.5%—

Multimodal Not comparable

C4ai Aya Expanse 8b: —, Grok 4.5: 37.6 (#72)

BenchmarkC4ai Aya Expanse 8bGrok 4.5
LMArena Vision—1288
Blueprint-Bench 2—27.3%
Furniture Assembly—22.5%
LMArena Document—1452

Multilingual Grok 4.5 leads

C4ai Aya Expanse 8b: 36.1 (#242), Grok 4.5: 54.4 (#42)

BenchmarkC4ai Aya Expanse 8bGrok 4.5
LMArena Non-English11801440
LMArena Chinese11811496
LMArena German11881446
LMArena Japanese11201428
LMArena Russian11971448
LMArena French—1456
LMArena Korean—1404
LMArena Spanish—1450

Instruction Following Grok 4.5 leads

C4ai Aya Expanse 8b: 60.1 (#253), Grok 4.5: 76.0 (#48)

BenchmarkC4ai Aya Expanse 8bGrok 4.5
LMArena Instruction Following11551446

Long Context Grok 4.5 leads

C4ai Aya Expanse 8b: 36.1 (#236), Grok 4.5: 44.8 (#56)

BenchmarkC4ai Aya Expanse 8bGrok 4.5
LMArena Longer Query11911463

Writing & Preference Grok 4.5 leads

C4ai Aya Expanse 8b: 39.0 (#250), Grok 4.5: 65.8 (#42)

BenchmarkC4ai Aya Expanse 8bGrok 4.5
LMArena Text11851448
LMArena Creative Writing11681442
LMArena Multi-Turn11601456
EQ-Bench Creative Writing—1579

Frequently asked questions

Is C4ai Aya Expanse 8b better than Grok 4.5?

Grok 4.5 is the stronger model overall, scoring 55.0 to 34.9 on the Noometry Index.

Is C4ai Aya Expanse 8b or Grok 4.5 better for coding?

Grok 4.5 scores higher on coding benchmarks: 52.2 versus 33.8 in the Noometry coding category.

How many benchmarks do C4ai Aya Expanse 8b and Grok 4.5 share?

14 benchmarks have published results for both models. C4ai Aya Expanse 8b has 15 scored results on Noometry and Grok 4.5 has 52.

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