GPT-5.6 API: Sol vs Terra vs Luna — Pricing and How to Choose (2026)
GPT-5.6 ships as three tiers. All at 90% of list on cocodot, metered, Alipay or card. Real prices, the surprising Sol-vs-5.5 comparison, and a tiering strategy that halves bills.
One generation, three compute tiers
GPT-5.6 is a family, not a single model. Sol targets the hardest reasoning, coding and research work; Terra balances capability and cost for everyday use; Luna is built for speed and volume. All three carry 1050K context and tool calling. The right question is not which is strongest — it is which tasks deserve which tier's price.
The counterintuitive fact: the new flagship is cheaper
After OpenAI's Aug 25 repricing, Sol lists at $4/$20 and cocodot serves it at $3.6/$18 — output at two-thirds of last-gen GPT-5.5's $27. Unless you need version pinning, switching mog-6 to mog-8-s is free money. 5.5 stays available; no forced migration.
Luna, the underrated volume engine
At $0.18 per million input tokens, Luna is the cheapest GPT here. Batch content processing, classification, summarization, support bots, the chore nodes of an agent graph. The $0.5 signup credit runs roughly 1.2M tokens of mixed traffic on Luna — enough to trial your whole pipeline before paying.
Two-minute setup
OpenAI-compatible: base_url https://cocodot.co/api/ai/v1, model mog-8-s / mog-8-t / mog-8-l (official names auto-route). Alipay or card, metered, no monthly fee. Long-context tiers are fully listed above — no hidden surcharge past 272K.
GPT-5.6 tiers + GPT-5.5 on cocodot (USD per M tokens, 90% of list)
| Model | ID | In / Out | Role |
|---|---|---|---|
| GPT-5.6 Sol | mog-8-s | $3.6 / $18 (>272K: $7.2/$27) | Flagship: reasoning, code, research |
| GPT-5.6 Terra | mog-8-t | $1.8 / $10.8 (>272K: $3.6/$16.2) | Balanced daily driver |
| GPT-5.6 Luna | mog-8-l | $0.18 / $1.08 (>272K: $0.36/$1.62) | Volume: high-frequency, cost-sensitive |
| GPT-5.5 | mog-6 | $4.5 / $27 (>272K: $9/$40.5) | Previous flagship, still available |