What does GPT-5.6 actually cost?
Tier prices, caching and real costs
Sol $5/$30, Terra $2/$12, Luna $0.20/$1.20 — updated after the 2026-07-30 price cut. Real cost still depends on cache hit rates.
OpenAI cut Luna 80% to $0.20/$1.20 and Terra 20% to $2/$12. Sol stays $5/$30 with Fast mode. Track ongoing changes on the Luna price tracker.
Open the GPT-5.6 Luna price trackerOfficial price table (per 1M tokens)
Cache writes cost 1.25x the input rate; cached reads get a 90% discount. All tiers share the 1.05M API context and 128K max output.
| Tier | Input | Output | Cache write (1.25x) | Cache read (−90%) |
|---|---|---|---|---|
| gpt-5.6-sol | $5 | $30 | $6.25 | $0.50 |
| gpt-5.6-terra | $2 | $12 | $2.50 | $0.20 |
| gpt-5.6-luna | $0.20 | $1.20 | $0.25 | $0.02 |
The GA caching upgrades are worth designing for
GPT-5.6 ships more predictable prompt caching at GA: explicit cache breakpoints (you decide where the prefix splits) and a 30-minute minimum cache life. For agent workflows that means pinning system prompts and tool definitions as the cached prefix can cut long-session input costs by up to 90%.
Three reproducible cost examples
Line-by-line at official rates — swap in your own volumes to check.
Everyday agent session (Terra)
800K input + 60K output on Terra: 0.8 x $2 + 0.06 x $12 = $1.60 + $0.72 = about $2.32 (short-context list rates as of 2026-08-02).
Hard task (Sol, high cache hit)
500K input (400K of it cached reads) + 50K output: 0.1 x $5 + 0.4 x $0.50 + 0.05 x $30 = $0.50 + $0.20 + $1.50 = about $2.20. Caching brings a Sol deep-dive close to Terra's uncached price.
Bulk light tasks (Luna)
1,000 calls at 10K input + 1K output each (10M input + 1M output): 10 x $0.20 + 1 x $1.20 = about $3.20 on Luna after the cut.
How the prices compare
Sol ($5/$30) matches Claude Opus 4.8 ($5/$25) on input and runs slightly higher on output; Terra ($2/$12 after the 2026-07-30 cut) is the everyday default; Luna ($0.20/$1.20) is about 1/25 of Sol list price for high-volume work. As of 2026-08-02, OpenAI list rates separate flagship capability from flagship spend.
Prices and usage on QCode
QCode's /models page shows live rates matching OpenAI's official prices, and usage inside your plan is metered per token at those rates. The three tiers share one API key and one quota with GPT-5.5, Claude and Gemini — low-latency access from mainland China with local payment, on plans from $8.57/mo.
Pricing FAQ
How exactly is caching billed?
Cache writes cost 1.25x the input rate (Sol $6.25, Terra $2.50, Luna $0.25 per 1M as of 2026-08-02). Cache reads stay about 10% of input (Sol $0.50, Terra $0.20, Luna $0.02).
Is long context billed extra?
There is no long-context surcharge in the official price list: within the 1.05M API window everything bills at the table rates. Filling the window does grow input cost linearly, of course — the lever is caching your prefix, not truncating context.
Does switching tiers affect billing or quota?
No. The tiers are just different model ids, each billed at its own rate against the same quota. You can mix them per request in one project — say Sol to plan, Terra to execute, Luna for batch work.
Do QCode prices match OpenAI's official rates?
Yes. The /models page shows the three tiers at official rates (Sol $5/$30, Terra $2/$12, Luna $0.20/$1.20 as of 2026-08-02).
Use GPT-5.6 at official rates
All three GPT-5.6 tiers bill at official rates inside a QCode monthly plan — from $8.57/mo, month to month, cancel whenever.