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PricesCompare → GPT-5.6 Sol vs Gemini 3.7 Flash

GPT-5.6 Sol vs Gemini 3.7 Flash: API cost compared

GPT-5.6 Sol lists at $2.500 in / $15.00 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
3.8x
at 3:1 in:out

Side by side

GPT-5.6 SolGemini 3.7 Flash
ProviderOpenAIGoogle
Input per 1M$2.500$0.750
Output per 1M$15.00$3.750
Cached input per 1M$0.250not published
Context window400k1M
Blended per 1M (3:1)$5.625$1.500

Monthly cost by workload

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

WorkloadGPT-5.6 SolGemini 3.7 FlashCheaperDifference
Customer support chatbot$366.00$133.12Gemini 3.7 Flash$232.88 (64%)
RAG document Q&A$490.00$165.00Gemini 3.7 Flash$325.00 (66%)
Coding agent$261.25$120.00Gemini 3.7 Flash$141.25 (54%)
Bulk summarization$3,465$1,050Gemini 3.7 Flash$2,415 (70%)
Structured data extraction$4,675$1,781Gemini 3.7 Flash$2,894 (62%)
Long-form content generation$636.50$165.00Gemini 3.7 Flash$471.50 (74%)
Email triage agent$1,081$487.50Gemini 3.7 Flash$593.75 (55%)
Translation pipeline$4,112$1,069Gemini 3.7 Flash$3,043 (74%)
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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 6.0 for GPT-5.6 Sol 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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Cost calculator

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

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