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PricesCompare → Claude Opus 5 vs Gemini 2.5 Flash-Lite

Claude Opus 5 vs Gemini 2.5 Flash-Lite: API cost compared

Claude Opus 5 lists at $5.000 in / $25.00 out per 1M tokens. Gemini 2.5 Flash-Lite lists at $0.100 in / $0.400. 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 2.5 Flash-Lite
wins 8 of 8
Blended rate gap
57.1x
at 3:1 in:out

Side by side

Claude Opus 5Gemini 2.5 Flash-Lite
ProviderAnthropicGoogle
Input per 1M$5.000$0.100
Output per 1M$25.00$0.400
Cached input per 1M$0.500not published
Context window200k1M
Blended per 1M (3:1)$10.00$0.175

Monthly cost by workload

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

WorkloadClaude Opus 5Gemini 2.5 Flash-LiteCheaperDifference
Customer support chatbot$644.50$16.00Gemini 2.5 Flash-Lite$628.50 (98%)
RAG document Q&A$920.00$20.80Gemini 2.5 Flash-Lite$899.20 (98%)
Coding agent$462.50$14.80Gemini 2.5 Flash-Lite$447.70 (97%)
Bulk summarization$6,730$136.00Gemini 2.5 Flash-Lite$6,594 (98%)
Structured data extraction$8,725$225.00Gemini 2.5 Flash-Lite$8,500 (97%)
Long-form content generation$1,073$18.00Gemini 2.5 Flash-Lite$1,055 (98%)
Email triage agent$2,012$62.00Gemini 2.5 Flash-Lite$1,950 (97%)
Translation pipeline$7,024$118.50Gemini 2.5 Flash-Lite$6,905 (98%)
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How to read this

Gemini 2.5 Flash-Lite 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 4.0 for Gemini 2.5 Flash-Lite. 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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