Skip to content
Rival
How it worksPrivacyTerms
Explore all of Rival

Explore

  • Compare Models
  • All Models
  • Image Comparison
  • Audio Comparison
  • Image Generation
  • Best AI For...
  • Arena
  • API Pricing
  • Challenges

Discover

  • SubjectiveBench
  • Research
  • Research downloads
  • Rival Kits
  • Find your AI taste
  • UI Glow-Up
  • VoiceLock
  • Cost Cutter
  • Agent skills
  • Benchmarks vs Vibes
  • Brief
  • Jailbreak
  • Model Updates
  • Provider Status
  • AI Creators

Connect

  • Methodology
  • Advertise
  • Partnerships
  • Privacy Policy
  • Terms
  • RSS Feed
  1. Home
  2. /
  3. Compare
  4. /
  5. Muse Spark 1.3 ContributorvsRiverflow V2 Fast
Updated Sep 2026

Muse Spark 1.3 ContributorvsRiverflow V2 Fast

Muse Spark 1.3 Contributor has a larger context window than Riverflow V2 Fast (1.0M tokens vs 8K tokens).

Muse Spark 1.3 Contributor and Riverflow V2 Fast compared across 2 shared prompts
SpecMuse Spark 1.3 ContributorRiverflow V2 Fast
Input price$0.1/M tokens—
Output price$0.2/M tokens—
Context window1.0M tokens8K tokens
WeightsClosed—
Free API (OpenRouter)NoNo
ReleasedSep 2026Feb 2026
Our Verdict
Muse Spark 1.3 Contributor
Muse Spark 1.3 Contributor
Riverflow V2 Fast
Riverflow V2 FastRunner-up

Not enough votes to call it. On the specs, Muse Spark 1.3 Contributor has the edge: newer, bigger context window, major provider backing.

Too close to call
API pricing

Cost per 1M tokens

Muse Spark 1.3 Contributor
Input
$0.10
Output
$0.20
Riverflow V2 Fast
Input
—
Output
—
Where to run it

2 hosts

Muse Spark 1.3 Contributor1 host
HostInOutContextUptime
Meta$0.10 in·$0.20 out·1M·100% up
Riverflow V2 Fast1 host
HostInOutContextUptime
SSourceful$0 in·$0 out·8k·100% up

Per million tokens. Prices and uptime via OpenRouter, checked 21 Sep 2026.

Research

What we learned reading every model

FAQ

Common questions

Muse Spark 1.3 Contributor is developed by Meta AI while Riverflow V2 Fast is developed by Sourceful. Muse Spark 1.3 Contributor has a 1.0M token context window vs Riverflow V2 Fast's 8K. You can compare their actual outputs across 2 challenges on Rival to see how they differ in practice.

It depends on your use case. Muse Spark 1.3 Contributor and Riverflow V2 Fast each have strengths in different areas. Rival lets you compare their real outputs side-by-side across 2 challenges so you can judge which fits your needs best.

This page shows a side-by-side comparison of Muse Spark 1.3 Contributor and Riverflow V2 Fast across shared challenges. You can vote on which model produced the better output in a blind duel. Browsing and voting are free. No account is needed to look; signing in only saves your votes and likes.

Keep exploring

More comparisons

Against the newest arrivals

Muse Spark 1.3 Contributor logoGPT-6 Astra Pro logo
Muse Spark 1.3 Contributor vs GPT-6 Astra ProLanded Sep 2026
Riverflow V2 Fast logoGPT-6 Astra logo
Riverflow V2 Fast vs GPT-6 AstraLanded Sep 2026
Muse Spark 1.3 Contributor logoClaude Fable 5.1 logo
Muse Spark 1.3 Contributor vs Claude Fable 5.1Landed Sep 2026
Riverflow V2 Fast logoMuse Spark 1.3 logo
Riverflow V2 Fast vs Muse Spark 1.3Landed Sep 2026
Muse Spark 1.3 Contributor logoHy4 Preview logo
Muse Spark 1.3 Contributor vs Hy4 PreviewLanded Sep 2026
Riverflow V2 Fast logoGemini 3.8 Flash logo
Riverflow V2 Fast vs Gemini 3.8 FlashLanded Sep 2026
Muse Spark 1.3 Contributor logoMercury 2.5 Preview logo
Muse Spark 1.3 Contributor vs Mercury 2.5 PreviewLanded Sep 2026
Riverflow V2 Fast logoGranite 4.2 8B logo
Riverflow V2 Fast vs Granite 4.2 8BLanded Sep 2026

Same lab, same size, long tail

Muse Spark 1.3 Contributor logoMuse Spark 1.3 logo
Muse Spark 1.3 Contributor vs Muse Spark 1.3Same lab
Muse Spark 1.3 Contributor logoMuse Spark 1.1 logo
Muse Spark 1.3 Contributor vs Muse Spark 1.1Same lab
Riverflow V2 Fast logoOx Alpha logo
Riverflow V2 Fast vs Ox AlphaSame size
Riverflow V2 Fast logoMiniMax M3 logo
Riverflow V2 Fast vs MiniMax M3Same size
Muse Spark 1.3 Contributor logoPolaris Alpha logo
Muse Spark 1.3 Contributor vs Polaris AlphaSame size
Riverflow V2 Fast logoPony Alpha logo
Riverflow V2 Fast vs Pony AlphaSame size
Muse Spark 1.3 Contributor logoQuasar Alpha logo
Muse Spark 1.3 Contributor vs Quasar AlphaSame size
Riverflow V2 Fast logoQwen Plus 0728 logo
Riverflow V2 Fast vs Qwen Plus 0728Same size

Model pages

Muse Spark 1.3 Contributor logo
Muse Spark 1.3 Contributor58 outputs, specs and price
Riverflow V2 Fast logo
Riverflow V2 Fast2 outputs, specs and price
Rival
How it worksPrivacyTerms
Explore all of Rival

Explore

  • Compare Models
  • All Models
  • Image Comparison
  • Audio Comparison
  • Image Generation
  • Best AI For...
  • Arena
  • API Pricing
  • Challenges

Discover

  • SubjectiveBench
  • Research
  • Research downloads
  • Rival Kits
  • Find your AI taste
  • UI Glow-Up
  • VoiceLock
  • Cost Cutter
  • Agent skills
  • Benchmarks vs Vibes
  • Brief
  • Jailbreak
  • Model Updates
  • Provider Status
  • AI Creators

Connect

  • Methodology
  • Advertise
  • Partnerships
  • Privacy Policy
  • Terms
  • RSS Feed