A side-by-side comparison of GPT-5.6 Luna and GPT-6 Astra: input/output pricing, capabilities and available endpoints, served live from openbat.ai. Both are reachable with the same API key.
| Item | GPT-5.6 Luna | GPT-6 Astra |
|---|---|---|
| Input (per 1M tokens) | $0.13 | $6.5 |
| Output (per 1M tokens) | $0.78 | $32.5 |
| Cache read explicit (per 1M tokens) | $0.013 | $0.65 |
| Cache write 5m (per 1M tokens) | $0.1625 | $8.125 |
| Item | GPT-5.6 Luna | GPT-6 Astra |
|---|---|---|
| Context window | 922,000 | 922,000 |
| Max output | 128,000 | 128,000 |
| Item | GPT-5.6 Luna | GPT-6 Astra |
|---|---|---|
| function_calling | Yes | Yes |
| prompt_caching | Yes | Yes |
| vision | Yes | Yes |
On input, GPT-5.6 Luna is cheaper ($0.13 vs $6.5 per 1M tokens). On output, GPT-5.6 Luna is cheaper ($0.78 vs $32.5 per 1M tokens). All prices are per million tokens in USD.
both support function_calling, prompt_caching, vision.
Yes. Both are available on openbat.ai through one API key and the same OpenAI-compatible endpoint — switching means changing the model field from "gpt-5.6-luna" to "gpt-6-astra", nothing else.
Both are available on openbat.ai 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.