Claude Sonnet vs Opus Pricing — When to Pay for Opus

Last verified: July 21, 2026

Short path: Compare live Sonnet and Opus rates on Claude API or migrate via cheap Claude API.

Teams searching claude sonnet vs opus pricing or claude opus too expensive usually run agents on Opus by default. Opus is Anthropic's strongest tier — but Sonnet completes many production tasks at roughly 40% lower token cost.

This guide compares Claude Sonnet 4.6 and Claude Opus 4.8 with official reference rates, LumeAPI catalog prices, escalation patterns, and Python examples on an OpenAI-compatible endpoint.

LumeAPI is an independent third-party gateway, not Anthropic.

Quick Answer

Model	Anthropic standard	LumeAPI catalog	Best for
Sonnet 4.6	$3 / $15 per 1M in/out	$1.80 / $9.00	Coding, agents, daily copilots
Opus 4.8	$5 / $25 per 1M in/out	$3.00 / $15.00	Hard reasoning, complex agents

Rule: Default to Sonnet. Route to Opus only when Sonnet fails your eval set or task SLA — not on every hop.

For 100M input + 20M output tokens per month:

Model	Anthropic standard	LumeAPI	Monthly saving vs official
Sonnet 4.6	$600	$360	$240
Opus 4.8	$1,000	$600	$400

Sonnet vs Opus — capability split

Claude Sonnet 4.6

Anthropic positions Sonnet as the balanced tier for coding, analysis, and agents.

Use Sonnet when:

Tool-calling agents run many steps per user task
Coding copilots need strong quality at scale
Document Q&A fits in moderate context
Cost per successful task matters more than peak capability

Claude Opus 4.8

Opus targets difficult coding, long-running agents, and professional analysis.

Use Opus when:

Sonnet fails repeated eval cases on hard reasoning
A single Opus call replaces several failed Sonnet retries
Legal, research, or architecture tasks need maximum judgment

Do not use Opus for classification, routing, or simple rewriting — that is how opus too expensive bills happen.

Cost per agent task (illustrative)

Agent task: 40,000 input + 6,000 output tokens (one hop):

Model	Anthropic standard	LumeAPI
Sonnet 4.6	~$0.21	~$0.126
Opus 4.8	~$0.35	~$0.21

An agent with 8 Sonnet hops ≈ one Opus hop in token cost — but Opus may finish in fewer steps on hard tasks. Measure cost per successful task, not per call.

Escalation pattern (recommended)

text

User request
  → Sonnet (plan + tools)
  → if eval_failed or complexity_score > threshold
      → Opus (single retry)
  → else Sonnet (finalize)

Log model id per hop in application metrics and Usage.

Python: Sonnet default, Opus escalation

python

import os
from openai import OpenAI

client = OpenAI(
    api_key=os.environ["LUMEAPI_KEY"],
    base_url="https://api.lumeapi.site/v1",
)

SONNET = "claude-sonnet-4-6"
OPUS = "claude-opus-4-8"

def complete(messages: list, hard: bool = False) -> str:
    model = OPUS if hard else SONNET
    r = client.chat.completions.create(model=model, messages=messages)
    return r.choices[0].message.content

Sonnet vs Opus pricing table (per 1M tokens)

Tier	Official input	Official output	LumeAPI input	LumeAPI output
Sonnet 4.6	$3.00	$15.00	$1.80	$9.00
Opus 4.8	$5.00	$25.00	$3.00	$15.00
Opus 4.7	$5.00	$25.00	$3.00	$15.00

Anthropic Batch API and prompt caching can beat standard real-time rates for async or heavily cached workloads. Compare total task cost, not list price alone.

When official Anthropic may still win

Heavy prompt cache hits on repeated system prompts
Batch jobs with 50% token discounts
Features not exposed through third-party gateways

FAQ

Is Claude Opus worth it over Sonnet?

Yes — for hard steps that Sonnet cannot complete reliably. No — as a default for every agent hop.

What about Claude Sonnet 5?

Sonnet 5 launched with introductory pricing in mid-2026. Verify Anthropic's current list and whether your gateway catalogs it before migrating budgets.

How does this compare to GPT or Gemini?

See LLM API pricing comparison 2026 and cut Claude API costs.

Next steps

Audit last 7 days of Usage — what % of calls are Opus?
Move routing and classification to Sonnet (or cheaper tiers).
Reserve Opus for a labeled hard queue with eval gates.