PyyanThe AI Index

Pyyan / Open-Weight Models / Muse Spark Open

Muse Spark Open

The largest American open weights, under a licence with a revenue trigger.

currentMeta ↗Verified 2026-10-20

816B

total, 42B active

Specifications

Context1Msource · as of 2026-10-20
Input ($/Mtok)Weights onlysource · as of 2026-10-20
Output ($/Mtok)Weights onlysource · as of 2026-10-20
LicenceMuse Model Licensesource · as of 2026-10-20
Max outputNot publishedsource · as of 2026-10-20
Parameters816B total, 42B activesource · as of 2026-10-20
Released15 Oct 2026source · as of 2026-10-20
Model IDmeta-models/Muse-Spark-Open-816B-A42Bsource · as of 2026-10-20

Official links

Muse Spark Open model pageMeta official site

What matters

  • Text, image, video and audio in, text out, with a 1M token context
  • Muse Model License, not open source: attribution required, and a separate agreement above $20m of model-service revenue
  • About 1.5TB in BF16, or two Mac Studios at 4-bit

Best for multimodal work you host yourself.

Compare with

All 5 side by side →

Muse Spark Open vs Qwen3.8-Flash-Next →Muse Spark Open vs DeepSeek V4.1 Flash →Muse Spark Open vs DeepSeek V4-Pro →Muse Spark Open vs MiMo-V2.6-Pro →Muse Spark Open vs MiMo-V2.6-Flash →

Also in Open-Weight Models

Qwen3.8-Flash-Next · AlibabaDeepSeek V4.1 Flash · DeepSeekDeepSeek V4-Pro · DeepSeekMiMo-V2.6-Pro · XiaomiMiMo-V2.6-Flash · Xiaomi