Compare Models

Muse Spark 1.3

Muse Spark 1.3 is a model from Meta, released September 2, 2026. It ranks #19 of 45 models on the Vals Index with 53.20%. Its best result is #3 of 76 on Harvey's Legal Agent Benchmark.

Release Date: Sep 2, 2026

Developer Meta  🇺🇸
Context Window 1M
Max Output Tokens 131k
Token Costs (in/out) $1.25/4.25
Weights Private
Input Modalities

Accuracy

53.20 % ± 1.07

Cost / Test (Vals Index)

$ 3.376

Latency

32 min 46 s

Fallback Rate 0.00%
Refusal Rate 0.13%
Vals Index
BenchmarksAccuracyRankings
Vals Index

53.20%

±1.07
19/45
Code Migration

27.58%

±4.07
42/75
CyberBench v1.1

69.41%

±5.76
24/45
EMB

62.71%

±2.96
29/72
Finance Agent (v2)

58.90%

±0.44
6/76
Legal Research Bench

40.87%

±3.42
24/75
ProofBench v1.1

55.00%

±5.00
25/48
Tax Agent Bench

35.97%

±3.42
9/67
Vibe Code Bench v1.1

82.86%

±2.90
17/110
Harvey's Legal Agent Benchmark

22.92%

±3.42
3/76
IOI

43.94%

±1.45
31/42
ProgramBench

0.50%

±0.50
22/63
Terminal-Bench 4.0

10.61%

±1.75
33/45
Terminal-Bench Science

4.29%

±2.44
23/39
Proprietary BenchmarksAcademic BenchmarksIndustry Partners
Vals
Default Provider : Meta
Temperature: 1
Top P: Default
Top K: Default
Max Output Tokens: 131,072
Reasoning Effort: xhigh

Compared with

Muse Spark 1.3 vs Claude Opus 4.8 11 shared benchmarks Muse Spark 1.3 vs Grok 4.7 14 shared benchmarks Muse Spark 1.3 vs GPT-5.6 Luna 14 shared benchmarks Muse Spark 1.3 vs Gemini 3.8 Flash 14 shared benchmarks Muse Spark 1.3 vs GPT-6 Sol 14 shared benchmarks Muse Spark 1.3 vs Claude Sonnet 5 14 shared benchmarks Muse Spark 1.3 vs GPT-5.6 Terra 14 shared benchmarks Muse Spark 1.3 vs GPT-5.6 Sol 14 shared benchmarks Muse Spark 1.3 vs MiMo V2.6 Flash 14 shared benchmarks Muse Spark 1.3 vs MiMo V2.6 Pro 14 shared benchmarks