Claude Sonnet 5 shipped alongside the new model generation and took the familiar mid-tier spot: faster and cheaper than the flagship, strong enough for most production workloads.
The price, in numbers
On November 10, 2026, in the Claudexia Premium channel, claude-sonnet-5 costs $0.52 per million input tokens and $1.98 per million output tokens. The flagship claude-opus-5 costs $1.08 and $4.12, about 2.1 times as much on both input and output.
At scale that gap adds up. What matters is whether Sonnet handles your task without Opus.
Where Sonnet 5 matches Opus
- everyday agentic coding: multi-file edits, tests, refactors that follow a clear plan
- API integrations, client code generation from docs
- answering over long context: PR review, ticket summarization, questions about a codebase
- routine agent steps where the task is already well specified
Sonnet 5 holds long context and follows instructions cleanly. That covers most pipelines.
Where Opus earns its keep
The flagship pays off when a task can't be broken into clear steps ahead of time: an unfamiliar architecture that needs to be understood as a whole, a race condition with no working hypothesis, planning under a pile of conflicting constraints. Opus reasons deeper there, and on tasks like these paying about twice the Sonnet price is usually justified.
If you're not sure, start with Sonnet. It either solves the task or fails visibly, and switching to Opus after that costs one extra call.
A working example
Anthropic Messages API:
from anthropic import Anthropic
client = Anthropic(
api_key="sk_cdx_your_key_here",
base_url="https://api.claudexia.tech",
)
message = client.messages.create(
model="claude-sonnet-5",
max_tokens=1024,
messages=[{"role": "user", "content": "Split this PR into logical commits."}],
)
print(message.content[0].text)
The same key also works with OpenAI Chat Completions:
from openai import OpenAI
client = OpenAI(api_key="sk_cdx_your_key_here", base_url="https://api.claudexia.tech/v1")
resp = client.chat.completions.create(
model="claude-sonnet-5",
messages=[{"role": "user", "content": "Split this PR into logical commits."}],
)
print(resp.choices[0].message.content)
Both formats run on one endpoint with one key, no need to rebuild infrastructure around a specific SDK.
Sonnet 5 versus Sonnet 4.6
Sonnet 4.6 is still in the Claudexia catalog (claude-sonnet-4-6, $0.68 / $2.48 per million input / output tokens in Premium on November 10, 2026), so nothing forces you to move. Sonnet 5 costs less, $0.52 / $1.98: to switch, set model to claude-sonnet-5. If your prompts were tuned for 4.6, run your typical requests on Sonnet 5 and compare against your own metric. Details in switching from Sonnet 4.6.
Checking it against your own numbers
Use the site calculator to compare models with your input and output volumes. Usage statistics are separate for each named key. The dashboard key API does not expose per-key budgets; bound automated workloads in your client.
In short
Sonnet 5 covers most production traffic at $0.52 / $1.98 per million input / output tokens. Opus 5 ($1.08 / $4.12) earns its place on tasks where the starting point isn't obvious. It costs about twice as much, so decide by the task.