GPT 5.6 Luna
GPT-5.6 Luna is the cheapest and fastest tier of OpenAI’s three-tier GPT-5.6 series (Sol, Terra, Luna) for high-volume, latency-sensitive tasks — available since July 30, 2026 at $0.20 / $1.20 per million tokens, roughly 80 percent below Sol. The 1-million-token context variant with 128,000 output tokens delivers frontier-adjacent agentic performance according to OpenAI, but falls off noticeably against its larger siblings on context recall beyond 512,000 tokens.
- Proprietary
- Frontier
- OpenAI
- Text
- Vision
- Real-Time
Sovereign Risk: MEDIUM The model is developed and hosted by a US-based company. Due to US jurisdiction, it is potentially subject to the CLOUD Act, which represents a moderate risk of data access by US authorities. Since the weights are proprietary and not distributed, there is no additional risk from disclosure of the weights themselves.
Key metrics
Score · Latency · Cost · Quality
- Total Score Silver
- 73.64
- Routine
- 45.12
- Reasoning
- 28.51
- LLM Judge Avg
- 3.63 / 5
- 100 Coverage
- Avg Task Duration
- 10.72s
- Real-Time
- Token Rate
- 87.57tok/s
- Output Rate
- P95 Latency
- 30.11s
- Top 5 %
- Total Tokens
- 80500
- Output Volume
- Cost per 1K
- $0.0012
- USD / 1K Requests
- Benchmark Cost
- $0.1
- Total · 80500 tok
Benchmark modules
10 modules · weighted · vs. model median & top performer
Token efficiency & latency
Consumption per module vs. model median
Token consumption per module
Performance profile
Key metrics – legend
Score
- Total Score
- Overall score derived from Routine and Reasoning scores. Basis for the fleet rank and tier assignment (Gold / Silver / Bronze / Standard).
- Routine
- Score for standard tasks: code generation, text transformation, structured outputs. Weighted by task complexity.
- Reasoning
- Score for analytical and logical tasks: multi-step problem solving, mathematical reasoning, structured argumentation.
- Rank
- Position in the fleet comparison, sorted by Total Score. Refers to the snapshot at the time of testing.
LLM Judge
- LLM Judge Ø
- Average quality rating by an independent judge model on a scale of 1–5.
- Coverage
- Share of tasks for which a judge rating is available. 100% means all responses were evaluated.
Latency & speed
- Avg. Task Duration
- Average time per task from the first to the last token of the response, measured across all benchmark tasks.
- Token Rate
- Output speed in tokens per second. Relevant for interactive applications and real-time streaming.
- P95 Latency
- 95th percentile of response times — shows outliers. Lower values mean fewer long wait times in edge cases.
Cost
- Cost per 1K
- API price per 1,000 output tokens in US dollars. Basis for cost calculation in production use.
- Benchmark Cost
- Total cost for the complete benchmark run of this model.