GPT-6 Luna vs Gemini 3.5 Flash-Lite

GPT-6 Luna (OpenAI) costs $0.10 per million input tokens and $0.50 per million output tokens; Gemini 3.5 Flash-Lite (Google) costs $0.30 and $2.50. GPT-6 Luna is 4.3× cheaper for a typical 3:1 input-to-output mix. Gemini 3.5 Flash-Lite has the larger context window (1.05M vs 922K tokens).

GPT-6 LunaGemini 3.5 Flash-Lite
ProviderOpenAIGoogle
Input / 1M tokens$0.10$0.30
Output / 1M tokens$0.50$2.50
Cached input / 1M$0.01$0.03
Blended (3:1)$0.20$0.85
Context window922K1.05M
Max output128K66K
VisionYesYes
Tool useYesYes
ReasoningYesYes
Listed sinceSep 27, 2026Jul 25, 2026

Cost per 1,000 requests

WorkloadGPT-6 LunaGemini 3.5 Flash-Lite
Chatbot reply2,000 input + 500 output tokens$0.45$1.85
RAG / search answer8,000 input + 700 output tokens$1.15$4.15
Long-document summary100,000 input + 2,000 output tokens$11.00$35.00

Blended price history

GPT-6 LunaGemini 3.5 Flash-Lite
$0$0.250$0.500$0.750$1.00Aug 26Sep 26Oct 26$0.200$0.850

Blended = (3 × input + output) ÷ 4, per million tokens. Each line starts when the model first appeared in the price list.

The companies

Related comparisons

List prices for each provider's own API (USD), taken daily from LiteLLM's public model price list. Batch, caching and committed-use discounts aren't reflected. Price alone says nothing about output quality; check benchmarks and your own evaluations before switching.