Claude Opus 5.5 vs Kimi K2.8 Preview

A side-by-side comparison of Claude Opus 5.5 and Kimi K2.8 Preview: input/output pricing, capabilities and available endpoints, served live from OpenCrow. Both are reachable with the same API key.

Pricing comparison

ItemClaude Opus 5.5Kimi K2.8 Preview
Input (per 1M tokens)$3.6$0.55
Output (per 1M tokens)$18$2.2
Cache read explicit (per 1M tokens)$0.18$0.1375
Cache write 5m (per 1M tokens)$4.5—

Specifications

ItemClaude Opus 5.5Kimi K2.8 Preview
Context window1,000,0001,048,576
Max output128,000131,072

Capability comparison

ItemClaude Opus 5.5Kimi K2.8 Preview
function_callingYesYes
prompt_cachingYesYes
reasoning—Yes
visionYes—
web_search—Yes

Which should you pick

Which is cheaper, Claude Opus 5.5 or Kimi K2.8 Preview?

On input, Kimi K2.8 Preview is cheaper ($3.6 vs $0.55 per 1M tokens). On output, Kimi K2.8 Preview is cheaper ($18 vs $2.2 per 1M tokens). All prices are per million tokens in USD.

Which has the larger context window, Claude Opus 5.5 or Kimi K2.8 Preview?

Kimi K2.8 Preview does — Claude Opus 5.5 accepts 1,000,000 input tokens and Kimi K2.8 Preview accepts 1,048,576.

What can Claude Opus 5.5 do that Kimi K2.8 Preview cannot?

both support function_calling, prompt_caching; only Claude Opus 5.5 supports vision; only Kimi K2.8 Preview supports reasoning, web_search.

Can I switch between Claude Opus 5.5 and Kimi K2.8 Preview without changing my code?

Yes. Both are available on OpenCrow through one API key and the same OpenAI-compatible endpoint — switching means changing the model field from "claude-opus-5-5" to "kimi-k2.8-preview", nothing else.

Both are available on OpenCrow under one API key — switching between them means changing the model field and nothing else, so you can use each where it fits rather than picking one.

Claude Opus 5.5 · Kimi K2.8 Preview · All models