GPT-6 Astra vs GPT-6 Luna

A side-by-side comparison of GPT-6 Astra and GPT-6 Luna: input/output pricing, capabilities and available endpoints, served live from J8API. Both are reachable with the same API key.

Pricing comparison

ItemGPT-6 AstraGPT-6 Luna
Input (per 1M tokens)$6.5$0.065
Output (per 1M tokens)$32.5$0.325
Cache read explicit (per 1M tokens)$0.65$0.0065
Cache write 5m (per 1M tokens)$8.125$0.08125

Specifications

ItemGPT-6 AstraGPT-6 Luna
Context window922,000922,000
Max output128,000128,000

Capability comparison

ItemGPT-6 AstraGPT-6 Luna
function_callingYesYes
prompt_cachingYesYes
visionYesYes

Which should you pick

Which is cheaper, GPT-6 Astra or GPT-6 Luna?

On input, GPT-6 Luna is cheaper ($6.5 vs $0.065 per 1M tokens). On output, GPT-6 Luna is cheaper ($32.5 vs $0.325 per 1M tokens). All prices are per million tokens in USD.

What can GPT-6 Astra do that GPT-6 Luna cannot?

both support function_calling, prompt_caching, vision.

Can I switch between GPT-6 Astra and GPT-6 Luna without changing my code?

Yes. Both are available on J8API through one API key and the same OpenAI-compatible endpoint — switching means changing the model field from "gpt-6-astra" to "gpt-6-luna", nothing else.

Both are available on J8API under one API key — switching between them means changing the model field and nothing else, so you can use each where it fits rather than picking one.

GPT-6 Astra · GPT-6 Luna · All models