Gemini 3 Flash Preview vs GPT-5.6 Luna

GPT-5.6 Luna is ~60% cheaper than Gemini 3 Flash Preview on output tokens. Both are capability tier 5.

Gemini 3 Flash PreviewGPT-5.6 Luna
VendorGoogleOpenAI
Capability tier5/85/8
Size classBALANCEDFAST
Parameters——
Context window—1,050,000
Input $/M$0.50$0.20
Output $/M$3$1.20 ✓
Cached input $/M$0.05$0.10

Which should you choose?

Both sit at capability tier 5, so GPT-5.6 Luna is usually the better value at ~60% lower output cost. Because they're the same tier, benchmark both on your own prompts before committing — list price rarely predicts task quality.

At 10M input + 10M output tokens / month
Gemini 3 Flash Preview: $35.00GPT-5.6 Luna: $14.00Δ $21.00/mo

FAQ

Is Gemini 3 Flash Preview cheaper than GPT-5.6 Luna?

GPT-5.6 Luna is the cheaper of the two on output tokens ($1.20/M vs $3/M), about 60% less.

Gemini 3 Flash Preview vs GPT-5.6 Luna: which has a bigger context window?

Both list the same context window (— tokens).

Which is more capable, Gemini 3 Flash Preview or GPT-5.6 Luna?

Both sit at the same capability tier (5/8) — pick on price, context, or benchmark them on your prompts.

Gemini 3 Flash Preview or GPT-5.6 Luna: which should I use?

Both sit at capability tier 5, so GPT-5.6 Luna is usually the better value at ~60% lower output cost. Because they're the same tier, benchmark both on your own prompts before committing — list price rarely predicts task quality.

How much more does Gemini 3 Flash Preview cost than GPT-5.6 Luna?

At 10M input + 10M output tokens per month, Gemini 3 Flash Preview runs about $35.00 and GPT-5.6 Luna about $14.00 — a difference of $21.00 per month at that volume.

Settle it on your own prompts

List prices only go so far — benchmark Gemini 3 Flash Preview and GPT-5.6 Luna on your actual workload for measured cost, latency and quality.

Pricing and specs maintained by Mintok's catalog watchers from public sources. Not investment advice. Methodology.