OpenAI Cuts GPT-5.6 Luna Prices 80% and Terra 20%
On July 30, 2026, OpenAI cut API prices for GPT-5.6 Luna by 80% (to $0.20/$1.20 per million tokens) and Terra by 20% (to $2/$12), held Sol pricing steady, and added a Fast mode for Sol up to 2.5× speed at 2× standard price—crediting efficiency gains from Sol on its own serving stack.
TLDR
OpenAI on July 30, 2026—three weeks after GPT-5.6 public launch—cut Luna API prices by 80% and Terra by 20%, left Sol list prices unchanged, and launched Fast mode for Sol in the API (up to 2.5× Standard speed at 2× Standard price). Lower Luna/Terra rates also reduce how usage is counted against Codex and ChatGPT Work quotas. OpenAI credits Sol-assisted efficiency work: ~20% lower serving costs and 15%+ token-generation efficiency via speculative decoding improvements.
New API pricing (per 1M tokens)
| Model | Prior (approx. launch) | July 30 | Change |
|---|---|---|---|
| GPT-5.6 Sol | $5 in / $30 out | Unchanged | — |
| GPT-5.6 Terra | $2.50 / $15 | $2 / $12 | −20% |
| GPT-5.6 Luna | $1 / $6 | $0.20 / $1.20 | −80% |
| Sol Fast mode | — | 2× Standard price, up to 2.5× speed | New SKU option |
Primary: OpenAI index post “Advancing the price-performance frontier with GPT-5.6” and same-day X thread; numbers corroborated by CNBC and VentureBeat.
Other product notes (same announcement)
- Auto-review in ChatGPT app and Codex CLI upgraded from GPT-5.4 → GPT-5.6 Luna; with new Luna price, OpenAI expects Auto-review ~10× cheaper.
- Subscription prices/quota budgets for ChatGPT/Codex unchanged; Terra/Luna consume fewer credits per unit of work.
- AWS pricing rollout noted as beginning the same day.
Competitive pressure
OpenAI frames the move as mission-aligned abundance of intelligence—but the market context is a price war: Chinese open-weight volume (Kimi K3, DeepSeek tiers), Anthropic Opus 5 cost positioning vs Fable, Google Gemini 3.6 Flash efficiency claims, and enterprise pushback on unconstrained token spend (CNBC). Cutting Luna hardest defends the high-volume tier while holding Sol as premium.
Why this story matters
Pricing is now a first-class model story, not a footnote. Repricing two of three GPT-5.6 tiers within three weeks of launch shows how fast cost curves move when open weights and rival Flash/Sonnet lines undercut US list prices. Developers should re-benchmark Luna/Terra vs Sol for agentic workloads; finance teams should re-model API and Work/Codex burn rates. Watch whether Sol eventually drops, how Fast mode affects quality/latency tradeoffs, and whether Anthropic/Google match within days.
Sources
- OpenAI: Advancing the price-performance frontier with GPT-5.6 (July 30, 2026)
- OpenAI on X: price cut + Sol Fast mode thread (July 30, 2026)
- CNBC: OpenAI cuts prices for two of its AI models (July 30, 2026)
- VentureBeat: Luna −80% / Terra −20% (July 30, 2026)
- OpenAI Developer Community: price drop announcement