Price comparison · checked October 12, 2026

GPT-6 Luna vs Gemini 3.1 Flash-Lite pricing

For a typical support chatbot (60,000 conversations a month), GPT-6 Luna costs $18.00 a month and Gemini 3.1 Flash-Lite costs $49.50. That makes GPT-6 Luna 2.8× cheaper for this workload.

GPT-6 LunaGemini 3.1 Flash-Lite
ProviderOpenAIGoogle
Input / 1M$0.10$0.25
Cached input / 1M$0.010–
Output / 1M$0.50$1.50
Context window1.05M1M
NotesShort-context rateAudio input $0.50

Monthly cost by workload

WorkloadGPT-6 LunaGemini 3.1 Flash-LiteDifference
Support chatbot
60,000 req · 1,500 in / 300 out
$18.00$49.50GPT-6 Luna 2.8× cheaper
Document summaries
20,000 req · 6,000 in / 400 out
$16.00$42.00GPT-6 Luna 2.6× cheaper
Coding assistant
30,000 req · 4,000 in / 800 out
$24.00$66.00GPT-6 Luna 2.8× cheaper
RAG search
100,000 req · 2,500 in / 250 out
$37.50$100GPT-6 Luna 2.7× cheaper

Standard rates, no caching or batch discounts. Sources: ai.google.dev · developers.openai.com

Try your own numbers

Start from a use case

1,000 tokens is about 750 English words. Input includes your system prompt, chat history and any retrieved documents.

GPT-6 Luna
OpenAICheapest
$18.00 /mo
Gemini 3.1 Flash-Lite
Google
$49.50 /mo

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