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PricesCompare → GPT-5.6 Terra vs Gemini 2.5 Flash-Lite

GPT-5.6 Terra vs Gemini 2.5 Flash-Lite: API cost compared

GPT-5.6 Terra lists at $1.000 in / $6.000 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
12.9x
at 3:1 in:out

Side by side

GPT-5.6 TerraGemini 2.5 Flash-Lite
ProviderOpenAIGoogle
Input per 1M$1.000$0.100
Output per 1M$6.000$0.400
Cached input per 1M$0.100not published
Context window400k1M
Blended per 1M (3:1)$2.250$0.175

Monthly cost by workload

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

WorkloadGPT-5.6 TerraGemini 2.5 Flash-LiteCheaperDifference
Customer support chatbot$146.40$16.00Gemini 2.5 Flash-Lite$130.40 (89%)
RAG document Q&A$196.00$20.80Gemini 2.5 Flash-Lite$175.20 (89%)
Coding agent$104.50$14.80Gemini 2.5 Flash-Lite$89.70 (86%)
Bulk summarization$1,386$136.00Gemini 2.5 Flash-Lite$1,250 (90%)
Structured data extraction$1,870$225.00Gemini 2.5 Flash-Lite$1,645 (88%)
Long-form content generation$254.60$18.00Gemini 2.5 Flash-Lite$236.60 (93%)
Email triage agent$432.50$62.00Gemini 2.5 Flash-Lite$370.50 (86%)
Translation pipeline$1,645$118.50Gemini 2.5 Flash-Lite$1,526 (93%)
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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 6.0 for GPT-5.6 Terra 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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Cost calculator

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