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PricesCompare → GPT-5.6 Sol vs Claude Sonnet 5

GPT-5.6 Sol vs Claude Sonnet 5: API cost compared

GPT-5.6 Sol lists at $2.500 in / $15.00 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
1.4x
at 3:1 in:out

Side by side

GPT-5.6 SolClaude Sonnet 5
ProviderOpenAIAnthropic
Input per 1M$2.500$2.000
Output per 1M$15.00$10.00
Cached input per 1M$0.250$0.200
Context window400k200k
Blended per 1M (3:1)$5.625$4.000

Monthly cost by workload

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

WorkloadGPT-5.6 SolClaude Sonnet 5CheaperDifference
Customer support chatbot$366.00$257.80Claude Sonnet 5$108.20 (30%)
RAG document Q&A$490.00$368.00Claude Sonnet 5$122.00 (25%)
Coding agent$261.25$185.00Claude Sonnet 5$76.25 (29%)
Bulk summarization$3,465$2,692Claude Sonnet 5$773.00 (22%)
Structured data extraction$4,675$3,490Claude Sonnet 5$1,185 (25%)
Long-form content generation$636.50$429.20Claude Sonnet 5$207.30 (33%)
Email triage agent$1,081$805.00Claude Sonnet 5$276.25 (26%)
Translation pipeline$4,112$2,810Claude Sonnet 5$1,302 (32%)
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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 6.0 for GPT-5.6 Sol 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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