Grok 4.5 vs Muse Spark Open: Benchmark Comparison

Grok 4.5 has the higher score on 1 of 4 shared benchmarks; Muse Spark Open leads on 3.

The largest observed score gap is 7.19 pts on Vibe Code Bench v1.1 , where Muse Spark Open leads.

Reported ±1 standard-error ranges overlap on 3 of 4 shared benchmarks with comparable uncertainty data. This is not a pairwise statistical significance test.

Open interactive comparison Read the methodology

Shared benchmark results

Scores and reported standard errors come from the latest visible Vals benchmark version available for both models.

Benchmark Grok 4.5 Muse Spark Open Gap Reported uncertainty
Legal Research Bench 37.98% ±3.37 38.46% ±3.38 0.48 pts Reported ±1 SE ranges overlap
Tax Agent Bench 24.86% ±3.12 26.32% ±2.65 1.47 pts Reported ±1 SE ranges overlap
Terminal-Bench 4.0 8.59% ±1.34 6.57% ±0.51 2.02 pts Reported ±1 SE ranges do not overlap
Vibe Code Bench v1.1 69.00% ±4.48 76.19% ±3.32 7.19 pts Reported ±1 SE ranges overlap

Performance by category

Category Grok 4.5 average Muse Spark Open average
Legal 37.98% 38.46%
Finance 24.86% 26.32%
Coding 38.79% 41.38%

Cost and latency

Cost per test appears only where the benchmark reports it for both models. Latency is the measured completion time for that benchmark.

Benchmark Grok 4.5 cost Muse Spark Open cost Grok 4.5 latency Muse Spark Open latency
Legal Research Bench $1.09 $1.56 15m54s 29m23s
Tax Agent Bench $0.47 $0.88 4m44s 11m42s
Terminal-Bench 4.0 $5.52 $7.26 33m43s 2h04m
Vibe Code Bench v1.1 $4.10 $1.66 13m50s 31m09s

Results available only for Grok 4.5

  • LegalBench
  • MortgageTax
  • TaxEval v2
  • MedCode
  • MedScribe
  • ProofBench v1.1
  • GPQA Diamond
  • MMLU Pro
  • MMMU Pro
  • SAGE
  • IOI
  • LiveCodeBench
  • ProgramBench
  • SkillsBench
  • SWE-bench
  • CyberBench v1.1
  • SRE Bench
  • Time Horizon Index: KSP

Results available only for Muse Spark Open

  • Vals Finance Index
  • Vals Index
  • Vals Legal Index
  • HLAB-Vals-1.1
  • EMB v1.1
  • Finance Agent v2.1
  • Code Migration v1.1
Model details Grok 4.5 Model details Muse Spark Open