Kimi K3 vs Grok 4.5: side-by-side summary

Kimi K3 and Grok 4.5 are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.

Kimi K3, from moonshotai, has a 1,048,576-token context window and is priced at $2.80/M tokens input, $14/M tokens output on OpenRouter.

Grok 4.5, from SpaceXAI, has a 500,000-token context window and is priced at $2/M tokens input, $6/M tokens output on OpenRouter.

Context window

• Kimi K3: 1,048,576 tokens
• Grok 4.5: 500,000 tokens

Price

• Kimi K3: $2.80/M tokens input, $14/M tokens output
• Grok 4.5: $2/M tokens input, $6/M tokens output

Provided by

• Kimi K3: moonshotai
• Grok 4.5: SpaceXAI

• Kimi K3 model details, providers and pricing
• Grok 4.5 model details, providers and pricing