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PricesCompare → Claude Opus 5 vs Gemini 3.7 Flash

Claude Opus 5 vs Gemini 3.7 Flash: API cost compared

Claude Opus 5 lists at $5.000 in / $25.00 out per 1M tokens. Gemini 3.7 Flash lists at $0.750 in / $3.750. 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
Gemini 3.7 Flash
wins 8 of 8
Blended rate gap
6.7x
at 3:1 in:out

Side by side

Claude Opus 5Gemini 3.7 Flash
ProviderAnthropicGoogle
Input per 1M$5.000$0.750
Output per 1M$25.00$3.750
Cached input per 1M$0.500not published
Context window200k1M
Blended per 1M (3:1)$10.00$1.500

Monthly cost by workload

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

WorkloadClaude Opus 5Gemini 3.7 FlashCheaperDifference
Customer support chatbot$644.50$133.12Gemini 3.7 Flash$511.37 (79%)
RAG document Q&A$920.00$165.00Gemini 3.7 Flash$755.00 (82%)
Coding agent$462.50$120.00Gemini 3.7 Flash$342.50 (74%)
Bulk summarization$6,730$1,050Gemini 3.7 Flash$5,680 (84%)
Structured data extraction$8,725$1,781Gemini 3.7 Flash$6,944 (80%)
Long-form content generation$1,073$165.00Gemini 3.7 Flash$908.00 (85%)
Email triage agent$2,012$487.50Gemini 3.7 Flash$1,525 (76%)
Translation pipeline$7,024$1,069Gemini 3.7 Flash$5,955 (85%)
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How to read this

Gemini 3.7 Flash 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 Gemini 3.7 Flash. 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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