Claude Opus 5.5 vs Claude Sonnet 5.5

A side-by-side comparison of Claude Opus 5.5 and Claude Sonnet 5.5: input/output pricing, capabilities and available endpoints, served live from 聚合 AI 中转站. Both are reachable with the same API key.

Pricing comparison

ItemClaude Opus 5.5Claude Sonnet 5.5
Input (per 1M tokens)$3.6$1.8
Output (per 1M tokens)$18$9
Cache read explicit (per 1M tokens)$0.18$0.18
Cache write 5m (per 1M tokens)$4.5$2.25

Specifications

ItemClaude Opus 5.5Claude Sonnet 5.5
Context window1,000,0001,000,000
Max output128,000128,000

Capability comparison

ItemClaude Opus 5.5Claude Sonnet 5.5
function_callingYesYes
prompt_cachingYesYes
visionYesYes

Which should you pick

Which is cheaper, Claude Opus 5.5 or Claude Sonnet 5.5?

On input, Claude Sonnet 5.5 is cheaper ($3.6 vs $1.8 per 1M tokens). On output, Claude Sonnet 5.5 is cheaper ($18 vs $9 per 1M tokens). All prices are per million tokens in USD.

What can Claude Opus 5.5 do that Claude Sonnet 5.5 cannot?

both support function_calling, prompt_caching, vision.

Can I switch between Claude Opus 5.5 and Claude Sonnet 5.5 without changing my code?

Yes. Both are available on 聚合 AI 中转站 through one API key and the same OpenAI-compatible endpoint — switching means changing the model field from "claude-opus-5-5" to "claude-sonnet-5-5", nothing else.

Both are available on 聚合 AI 中转站 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 · Claude Sonnet 5.5 · All models