WeavePrism

Grok 4.1 Fast vs Kimi K2

Grok 4.1 Fast costs 74% less at typical usage ($0.28 vs $1.07 per 1M tokens). Kimi K2 scores higher on 6 of 11 tasks.

SpecGrok 4.1 FastKimi K2
Input /1M$0.20$0.60
Output /1M$0.50$2.50
Typical /1M$0.28$1.07
Context window2M256k
SpeedFastBrisk
PrivacyStandardSelf-host
Open weightsNoYes
Grok 4.1 Fast
Steady since we started tracking (Jul 13, 2026)
Steady since we started tracking (Jul 13, 2026)
Kimi K2
Steady since we started tracking (Jul 13, 2026)
Steady since we started tracking (Jul 13, 2026)

Quality by task

Coding82/87
Agents84/90
Reasoning84/88
Writing82/86
Chat86/86
Classify84/83
Extract84/84
Summarize85/86
Translate84/84
Vision84/30
General83/86

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Prices are list $/1M tokens, hand-maintained from public provider pricing. Task scores are benchmark-informed 0-100 estimates, not gospel — validate on your own evals before moving production traffic. Not affiliated with any model provider.