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PricesCompare → Claude Opus 5 vs Claude Sonnet 5

Claude Opus 5 vs Claude Sonnet 5: API cost compared

Claude Opus 5 lists at $5.000 in / $25.00 out per 1M tokens. Claude Sonnet 5 lists at $2.000 in / $10.00. Sticker price only tells you so much — below is what each actually costs across eight production workloads.

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Cheaper on more workloads
Claude Sonnet 5
wins 8 of 8
Blended rate gap
2.5x
at 3:1 in:out

Side by side

Claude Opus 5Claude Sonnet 5
ProviderAnthropicAnthropic
Input per 1M$5.000$2.000
Output per 1M$25.00$10.00
Cached input per 1M$0.500$0.200
Context window200k200k
Blended per 1M (3:1)$10.00$4.000

Monthly cost by workload

Caching applied at each workload's typical hit rate. This is where the two models actually separate.

WorkloadClaude Opus 5Claude Sonnet 5CheaperDifference
Customer support chatbot$644.50$257.80Claude Sonnet 5$386.70 (60%)
RAG document Q&A$920.00$368.00Claude Sonnet 5$552.00 (60%)
Coding agent$462.50$185.00Claude Sonnet 5$277.50 (60%)
Bulk summarization$6,730$2,692Claude Sonnet 5$4,038 (60%)
Structured data extraction$8,725$3,490Claude Sonnet 5$5,235 (60%)
Long-form content generation$1,073$429.20Claude Sonnet 5$643.80 (60%)
Email triage agent$2,012$805.00Claude Sonnet 5$1,207 (60%)
Translation pipeline$7,024$2,810Claude Sonnet 5$4,214 (60%)
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How to read this

Claude Sonnet 5 is cheaper on the majority of these workloads, but "majority" is not the decision. The output:input price ratio is 5.0 for Claude Opus 5 and 5.0 for Claude Sonnet 5. If your traffic is output-heavy — long-form drafting, translation — the model with the lower output price wins regardless of what the input price suggests. If you are input-heavy — RAG, bulk summarization, agents re-reading a codebase — the cached input rate matters more than either headline number.

Cost is also not the only axis. This site does not benchmark quality, latency, or rate limits, and a model that is 3x cheaper but needs two attempts per task is not cheaper. Use these numbers to size a bill, then validate on your own evals.

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Cost calculator

Enter your own numbers, or start from a workload preset. Costs are monthly and update as you type.

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