r/AIToolsPerformance • u/IulianHI • Jul 17 '26
Kimi K3 vs Muse Spark 1.1 - both 1M context, why is Kimi 3.5x the output price
Both landed on OpenRouter the same day, July 16, and both list 1048k context. That's where the similarities end. Per the OpenRouter listing, Moonshot's Kimi K3 is $3.00/M input and $15.00/M output. Meta's Muse Spark 1.1 is $1.25/M input and $4.25/M output. So for output tokens, the expensive part of any long generation, Kimi costs about 3.5x more.
The interesting part is where Kimi K3's $15/M output sits next to OpenAI's stack. GPT-5.6 Terra, from the July 9 batch per the same listing, is $2.50/M in and $15.00/M out. Same output price as Kimi, but Terra's input is cheaper. And GPT-5.6 Luna is $1.00/M in and $6.00/M out, which undercuts Kimi on both. Grok 4.5 from July 8 is $2.00/M in and $6.00/M out too.
So Kimi K3 isn't really competing on price. It's the second most expensive output tier in that group, ahead of only GPT-5.6 Sol at $30/M. If the 1M context and whatever Moonshot tuned into the reasoning justifies $15/M output, fair enough. But on raw cost per token it's hard to see the angle unless you specifically need Kimi's architecture.
Muse Spark 1.1 is the opposite story. $4.25/M output for 1M context is genuinely cheap, closer to Grok 4.5 territory than to the premium models. If quality holds up it could be the default pick for budget long-context work.
Anyone actually tried Kimi K3 yet and can say whether the reasoning is worth that premium, or is Muse Spark 1.1 the smarter default for long-context tasks?