Claude Sonnet 5.5 costs less: $2.50 less per 1M input tokens and $12.50 less per 1M output tokens. Both take images, call tools and reason before answering. Both read up to 1M tokens at once. Both run on one withConflux key.
| Claude Opus 5.5 | Claude Sonnet 5.5 | |
|---|---|---|
| Input, per 1M tokens | $5.00 | $2.50 |
| Output, per 1M tokens | $25.00 | $12.50 |
| Context | 1M tokens | 1M tokens |
| Can use | vision, tools, reasoning | vision, tools, reasoning |
| Typical answer, our gateway | Not measured yet | Not measured yet |
| First token | Not measured yet | Not measured yet |
Green = better on that row. Speed for every model: API speed.
At your price on withConflux. Change the numbers in the calculator below to match your traffic.
| Workload | Claude Opus 5.5 | Claude Sonnet 5.5 |
|---|---|---|
| Support chatbot 30,000 messages a month, 1,500 tokens in and 300 out each | $450.00 | $225.00 |
| Coding agent 2,000 tasks a month, 40,000 tokens in and 4,000 out each | $600.00 | $300.00 |
| Document summaries 10,000 documents a month, 8,000 tokens in and 600 out each | $550.00 | $275.00 |
from openai import OpenAI client = OpenAI(base_url="https://withconflux.com/v1", api_key="cflx_live_...") client.chat.completions.create(model="claude-sonnet-5-5", messages=[...]) # or "claude-opus-5-5"
Sign up free and call Claude Opus 5.5 and Claude Sonnet 5.5 with the same key. Each call shows its cost per key.
Claude Sonnet 5.5 is cheaper for both input and output.
On withConflux, yes: both are behind the same OpenAI-compatible endpoint. You change the model name.
No. One withConflux key calls both. With your own keys (BYOK) you can use your accounts instead, for €19 a month.
Prices are read from our live model list. Speed is recalculated every hour from the last 7 days. The date is on the page.